Want to visit Gunung Mulu National Park? Interested in seeing what three million bats flying out of a cave looks like? Here’s a guide to planning your epic adventure with everything that you need to know.
This blog post contains affiliate links - if you click on them and buy something we make a small commission. For more info please read our legal stuff.
If you are sneakily trying to plan your trip to Mulu at work and haven’t got time to read this mega post, just use the links below to get to the section that you want. Don’t say that we don’t love you.
As we strap on our harnesses and adjust our carabiners and helmets, Vincent gives me one of those looks. The look that says: “Remind me why we are doing this again?”
In a way, I can see his point. It’s an almost cliched glorious day outside, sun shining, birds chirping…the perfect weather for a relaxing walk and a picnic. And yet, despite all this beauty above ground, we are about to venture into a dark, cold and wet cave, possibly get soaked through to the bone by freezing water and be surrounded by huge and weird creepy crawlies and piles of bat guano. It doesn’t sound very appealing. I mean, it’s probably not a place that you’d suggest taking someone on a first date for instance. “Let’s kiss by this pile of bat shit crawling with spiders and cockroaches.” Uh, no.
But the truth is, there is a fascinating and stunningly beautiful hidden world beneath our feet. And I love exploring it. Maybe it’s the fact that I am under 4’11” and I feel an inescapable pull towards living my #BestTroglodyteLife. Or perhaps it is because caves are just so…epic. From the hidden underground churches in Turkey’s Cappadocia to the ornate caves of Phong Nha Kebang in Vietnam, a caving experience exposes you to some seriously phenomenal sights. And if that wasn’t enough, it can be quite the workout too. I mean, I really am flexing some cave related mega-guns right now as I type. I swear.
This time, our subterranean adventuring was going to take us into the depths of Gunung Mulu National Park in the heart of Malaysian Borneo. Over the course of this journey I’d see racer snakes, a swarm of bats so thick I initially mistook it for smoke, and caves so beautiful they looked like something out of a Salvador Dali painting. I put on my head torch and smiled at Vincent. I was ready to discover what lay beneath.
Gunung Mulu National Park
Located in the state of Sarawak in East Malaysia, Gunung Mulu National Park is a UNESCO World Heritage site of outstanding natural beauty. Dominated by three mountains, Gunung Mulu (2,376m), Gunung Api (1,750m) and Gunung Benarat (1,858m), the national park also boasts 554 square kilometres of primary rainforest, rivers and jungle streams. The area is also home to some of Sarawak’s last nomadic tribes as well as a wide range of wildlife, plant and flower species.
But adventurers from all over the globe often come to visit Mulu for something else: lying beneath the dense jungle is a honeycomb of underground caverns and rivers that make up one of the most extensive limestone cave systems in the world. Some of Mulu’s caves are even world record breakers: Deer Cave has the world’s second largest cave passage, whilst the Clearwater Cave System at Mulu is the eighth longest cave in the world. And if you still remain unimpressed, the Sarawak Chamber is the world’s largest natural chamber capable of holding 40 Boeing 747s wingtip to wingtip. Whoa.
How to get to Mulu
There really isn’t anything like flying into Mulu. As the tiny ATR 72 plane began its steep descent, I looked out of the window at a scene that could have been straight out of Jurassic Park (cue the theme music in my head). Below me I could see endless miles of forested mountains and coffee coloured rivers snaking their way across the landscape and out to sea. And then, in the distance, cut into the jungle was the tiniest runway I had ever seen. We really were in the middle of nowhere, but bizarrely still somewhere with surprisingly good aviation links. Go figure.
The gateway to Mulu National Park is via Miri in North East Sarawak. Flights are operated by the rural air service provider MAS Wings (a subsidiary of Malaysia Airlines) and the direct flight between Miri and Mulu takes just 30 minutes. There are about 15 flights per week on this route.
You can also fly from Kuching in Sarawak - this takes a bit longer at 1 hour and 35 minutes and there are seven flights per week via this route. Finally, if you are visiting Sabah (and if you haven’t done this already, I’d strongly suggest that it goes on your list of places to visit - think mountain climbing, wild orangutan spotting and a buzzing night life for starters) and want to fly to Mulu from there, you can hop on a flight from Kota Kinabalu which takes 55 minutes. These flights are more infrequent, with only three flights per week operating on this route.
In 2019, the cheapest return flight from Miri to Mulu cost £60 but prices increase over the peak season which runs from June to September. The other routes are a little pricier, with the cheapest flights starting at around £70 return from Kuching and Kota Kinabalu. The key thing is to book your flights as early as possible. We learned this the hard way: we booked two single flights from Miri to Mulu which cost us 319RM (£60), but our flights from Mulu to Kota Kinabalu cost us 513RM (£97), when they really should have been cheaper.
The local community of Mulu provides reliable and very cheap airport transfers costing 5RM (£0.90) per person to the hotels and lodges around the national park. You can also walk from the airport to your accommodation or the national park if you choose, which takes about 15-20minutes.
For those super adventurers, there is the possibility of hiking to Mulu via the ‘The Headhunters Trail’ which starts from the town of Limbang. The trail is well marked and maintained, however, the area is extremely isolated and the nearest town is very far away so it is recommended that you contact a licensed tour operator to arrange this if you want to take this route. Because going missing in a jungle is totally not cool.
If you do fly in via Miri and have a few hours to kill before your flight to Mulu, take a taxi or order a Grab car into town and get yourself to Khan’s Islamic restaurant. Our flight from Kuala Lumpur was so early that we didn’t have time to get a good breakfast, but we more than made up for it at Khan’s. Think delicious freshly made chappatis and chickpea curry. Yummeh!
Where to stay in Mulu National Park
We didn’t really have much time to plan our visit to Mulu, so for ease we decided to enquire about accommodation at Mulu National Park Headquarters via their website. That way we figured that we would also be on site for all the activities we wanted to do as well.
There are a variety of accommodation options at the park HQ including double rooms starting at 320RM (£60) per night for two people sharing; longhouse style accommodation with four single beds at 340RM (£64) per night for four people sharing and dormitories costing 58RM (£11) per bed per night. All rooms include a daily set breakfast. Once you send an enquiry via their website, they will send you an email confirming your booking details and information on how to transfer a 25% deposit to their bank account to secure your accommodation. You can also pay your deposit by credit card. Just remember to bring proof that you’ve paid the deposit along with you when you check-in so that they can take this amount off your final bill.
We honestly weren’t expecting much from this accommodation (it is in the middle of the jungle after all) and I have to admit that we were pleasantly surprised. Our room was really spacious, bright, clean and comfortable and had a lovely balcony and decking area outside. The bathroom was also super clean with plenty of hot water - exactly what you need after a day of hiking or adventure caving.
For those who desire 5* luxury even in the jungle, surprisingly, there is also something for you. The Mulu Marriott Resort and Spa is just five minutes down the road from the national park and has all the perks you would expect from a luxury hotel, including lavish cabin-style accommodation on stilts that offers views of the surrounding jungle; bathrooms with huge bathtubs and rain showers; satellite TV and WIFI. There’s also a spa (did you guess that from the hotel name?), a pool and a breakfast and dinner buffet offering a sumptuous array of dishes that will ensure that you are well fuelled ahead of all your activities. Of course, all of these perks come at a price: a standard deluxe room (not including breakfast) at the hotel starts at 515RM per night.
For the budget traveller, there are a number of really affordable locally run homestays and backpackers lodges located on the side of the main road leading up to the park HQ. A good list of budget accommodation is available here and some places charge as little as 35RM (£6.50) per night including breakfast.
Be aware that accommodation outside of the park HQ (excluding the Marriott) only have electricity for a few hours each day in the evening so if you are someone who needs a fan or aircon to sleep in hot countries, then this might not be the best option for you. On the other hand, tire yourself out completely during the day and you might just fall asleep as soon as your head hits the pillow at lights out.
What to pack for your Mulu adventure!
The official Mulu website has a basic guide on how to prepare for a trip to Mulu, including typical weather in the national park and some guidance on what to bring with you. Most people spend at least two to three days at Mulu - we stayed for four nights because we wanted to experience a number of different activities and didn’t want to feel too rushed. Although you won’t need much in terms of supplies on your trip (unless you are trekking the Pinnacles), I would recommend packing the following basics:
Comfortable lightweight clothing that is suitable for hiking and trekking and that you don’t mind getting dirty. I wore basic gym gear on most days and it also dried out quickly: there are often sudden downpours at Mulu, particularly in the afternoon and if you are outside you can quickly become soaked through (this happened to us more than once). Some adventure caving experiences also require you to swim/wade through rivers so quick-dry clothing is essential.
Some socks that you can pull over your trousers to stop leeches getting in and sucking your tasty, tasty blood.
A raincoat. Again to emphasise, it rains a lot.
A head torch or torchlight. These are particularly useful during night walks, adventure caving experiences and also when the electricity cuts out. We brought some really crappy ones with us and they fell apart half way through one of our trips. Don’t be like us. A good head torch is worth the investment. (Note: we were provided with proper head torches during the Racer Cave experience, even though the website says you need to bring your own torch. I am not sure why this is.)
First Aid kit and any personal medication you need. Bring everything from your ibuprofen to your anti-diarrhoea meds with you as there are no chemists in the area.
Cash. At Mulu, cash is KING because there are no ATMs or banks. So this is your chance to act like a true playa and bring all your cheese. (But no Benjamins ‘yo, it’s Malaysian ringgit only here). We brought 800RM to make sure we had more than enough to cover food and other expenses. You can however, pay for your activities at Mulu HQ via credit card.
Comfortable trainers with a good grip or trekking shoes. We wore trainers which worked out fine for us, even in the adventure caving experiences but mine could have done with a bit more grip. They also dried out quickly after we swam in them. If you don’t have the right kind of shoes, you can buy a pair of ‘Adidas kampong rubber shoes’ from the Mulu Park shop which are waterproof, have a decent grip and flexible sole that is suitable for climbing. Some people that we met in Mulu were able to borrow a pair of these shoes from their hosts at their homestays.
Insect repellant. There are some mozzies at Mulu, but not as many as you would expect.
A dry bag. To keep all your tech equipment bone dry. We bought one from the Mulu shop for 50RM as we realised we would need one to protect our camera. It would be cheaper to buy this elsewhere.
Note - if you are planning to climb the Pinnacles, it is worth reading this guide which tells you what to bring with you (particularly for the camping element of the trip) and what to expect from the experience.
Where to Eat
As we were staying within the national park itself, we ate most of our meals at Mulu Cafe. Our room came with breakfast included - there were pancakes and traditional Malaysian roti canai with dhal as well as Western breakfast staples such as eggs and toast. The menu options for lunch and dinner were fairly reasonably priced (although still twice what you’d pay anywhere else in Malaysia) and very tasty.
There are also great choices for vegetarians: I particularly liked ordering some of the vegetable side dishes for my main course including the vegetable coconut curry and paku jungle fern with ginger and garlic. Yums. Be aware that during bad weather, supplies sometimes don’t reach the park and so they can run out of certain ingredients: when we were there they didn’t have bananas for several days, much to Vincent’s dismay as he loves a good banana smoothie.
If you want to try something a bit different and cheaper, just outside the park is Good Luck Cave-fe Mulu. They serve a variety of Malaysian dishes such as laksa, tom-yum soup, nasi goreng and sweet and sour fish with rice for between 10-18RM. There’s also a number of Western food options and they serve beer as well (although it is expensive!).
Activities at Mulu
You’ve arrived! Now the fun really starts - you simply have to choose what you want to do and then, well, do it.
We booked most of our activities when we arrived at the Park HQ apart from two that we were advised to book in advance via email due to their popularity - the Night Walk and the Garden of Eden cave experience. Activities book up quickly, so I recommend that organising your itinerary at Mulu should be your priority as soon as you arrive, unless you have pre-booked all your experiences with a separate tour operator.
Activities at Mulu are divided into a number of categories:
Showcaves - these are easily accessible caves that still need to be visited with a guide, but include boarded walkways and some lighting. The Deer and Lang Caves, Clearwater Cave and Cave of the Winds are the four showcaves at Mulu.
Adventure Caves - these guided cave experiences require a certain level of physical fitness and you are equipped with a hard hat, ropes and torchlights. The experiences vary from beginner to advanced level and include some climbing, scrambling, hiking and swimming.
Trekking and Hiking - these include a guided night walk, a trekking and overnight camping experience, jungle trekking and Mulu canopy walk which is one of the longest tree based canopy walks in the world.
Extreme Adventures - this includes the Pinnacles trek and the trek to the summit of Gunung Mulu.
There are also a number of unguided and well signposted walks that you can do yourself around Mulu - the Park HQ will give you a map of the park when you book your activities that show you the various unguided walking trails and routes. You can also take a longboat ride down the river to visit indigenous settlements and nearby waterfalls.
After a bit of discussion, (yes, I promise there was discussion, I didn’t decide it ALL) we decided to book an adventure caving experience, a trek, a night walk, a trip to some of the other showcaves and the canopy experience. And if we could fit in some of our own walks and experiences, we’d do that too! It was that go hard or go home mentality: we were finally here, so we might as well pack in as much as we could (and also as much as our budget would allow).
Note: sometimes activities get cancelled due to heavy rainfall at Mulu. The guides will assess the weather before each activity and inform you whether it is safe to go ahead. Because tours can get cancelled at short notice, I would recommend that you add at least one buffer day on to your trip, so you can re-book an activity if necessary.
And so without further ado, here’s our itinerary over our 4 night, 5 day trip at Mulu National Park.
The Night Walk - For You Night Owls
Duration: 1-2 hours
Are you the kind of person who wants to know what kind of creepy crawlies lurk about once dusk has fallen? Or perhaps you see a small, dark hole and wonder what lives inside it? Then the night walk experience is for you.
It was just after 7pm when we gathered at the meeting point with our guide for our first activity at Mulu. It had rained and the rainforest was filled with the cacophony of buzzing insects. After checking that we all had the right footwear (the main paths around the park are all boarded but can become really slippery after the rain) and advising us not to wear insect repellant as it scares off the wildlife (who knew?) we set off.
The night walk encompasses a 1.5km circular route around the park. Our guide was extremely knowledgeable and as I expected, very observant, pointing out all sorts of hairy caterpillars, frogs and insects that I would have otherwise simply walked past.
The biggest surprise was seeing a stick insect the length of my forearm wandering nonchalantly about (I had no idea that they grew to be that large). There were also a number of mating pairs of stick insects, so I learned that April is perhaps the month that they like to get jiggy with it. Or maybe they are at it all the time. Horny devils.
The night walk is a great introduction to some of the creatures that inhabit Mulu National Park and also a good way to get familiar with the various walking trails you can do by yourself.
Pro-tip: use a camera with a flash on the night walk if you want to get really good pictures of the insects and animals that you see. I didn’t do this and I wished that I had. I didn’t repeat this mistake again when I went on another night walk in Kinabatangan.
Garden of Eden Valley Walk
Duration: Full day usually finishing around 5pm
This intermediate level tour also includes a visit to the Deer and Lang caves - as it’s a full day tour, you are advised to bring your own lunch and so we ordered a packed lunch from the Mulu Cafe while we were having our breakfast.
We started off at 9.30am on a 12km round trip that took us through the jungle and over rivers along a boarded walkway. There were eight of us in our group, including one guy, who I estimated to be in his early twenties, who was dressed in full army fatigues. This made me worry about exactly what kind of trek I had signed us up for.
The first stop after a 45 minute walk was Deer Cave, which contains the world’s second largest cave passage - 174 metres wide and 122 metres high. (It used to hold the world record but after a cave-off with Vietnam’s Hang Sơn Đoòng in 2009, was relegated to second place.)
Now, if the thought of venturing into any kind of cave makes you feel slightly claustrophobic, let me reassure you, Deer Cave is absolutely MAHOOSIVE. Once inside, I craned my neck to see if I could glimpse anything remotely resembling the ceiling of the cave and failed miserably. The space inside Deer Cave is supposedly five times the size of St Paul’s Cathedral. So…pretty big then?
Deer Cave also has 800 metres of boarded walkways inside it, which makes it quite easy to explore. As we wandered through, we could hear the gentle squeaking of the bats that were sleepily clinging to the vaulted cave roof above us. The largest part of the cave is actually home to three million bats from 12 different species (higher than any other single cave in the world) as well as a large number of swiftlets.
The bat residents have certainly made themselves at home, by basically pooing all over the place. The cave floor, handrails and steps were pretty much all covered in bat guano - in some areas of the cave the guano was literally metres high. As a result, Deer Cave has quite a pungent, ammonia-like smell, so if you aren’t a fan of strong smells, it might be advisable to cover your nose with a scarf. Our guide advised us to shine our torch onto some of the piles of guano and when we did, it looked as though it was moving. On closer examination we could just about see hundreds of cockroaches and spiders scuttling across it. Lovely.
I was taking my time, wandering along slowly and taking photos of absolutely everything. Our guide however, seemed to want to rush us through (something I find highly annoying on tours) and telling us that we could take photos later. Me being me, I ignored this and carried on as I was and seemingly pissed off some members of the group in the process. One girl hissed “they keep stopping to take photos” and then sped off with her friend at high speed. I didn’t really understand the rush - the cave or the jungle wasn’t going to be going anywhere.
And how could you not linger? The cathedral-like inside of Deer Cave is truly magnificent: sunlight streams into parts of the main chamber and in the widest part of the cave I felt like I was standing in the depths of a weird kind of valley. At a certain point, we turned around so we could see another of Deer Cave’s distinguishing (one could say, ‘presidential’) features: the silhouette of jutting rocks towards the mouth of the cave looks like Abraham Lincoln!
Our group had gone on ahead and so a few shutterclicks later, we sped after them. As we rounded a corner, the beautiful ‘Garden of Eden’ came into view and we found our group standing in a hushed silence. There was clearly time to take photos now. Ahead, we could see shafts of daylight and rich, verdant vegetation: a stark contrast to the darkness within the cave. This green oasis is thought to have been the result of a massive sinkhole, which let in enough light to enable plants to thrive. In keeping with the biblical theme, our guide then also pointed out the ‘Adam and Eve showers’ on the roof of the cave which spout columns of water 30 metres onto the riverbed below.
A jungle trek and some pretty waterfalls
The regular tour of Deer Cave would usually end here, but not for us. Our guide explained to us that we would have to cross the Eden river, which flows right near the Garden of Eden and into parts of Deer Cave. The water “was only chest high”, he said, so it would basically be wading through the river to get to the other side, where we would begin our jungle trek. “Carry your back packs above your heads” he advised, “so that your cameras, dry clothes and lunch doesn’t get wet”.
I looked at Vincent. Only chest high? I already knew that chest height on a normal person was going to be right over the top of my head. Vincent packed our camera and lunches into our dry bag and then everyone started to wade through. Apart from me. I swam and got out on the other side soaking from head to foot. Ah, the pitfalls of being an under height human.
Once we had crossed the river, we followed it for another hour or so, trekking through the jungle uphill. As we walked, I noticed a leech had decided to make love to my leg, so I stopped and flicked it off. As the terrain became steeper, some of our fellow group members were starting to fall behind, panting and red faced. I guess it’s pretty easy to storm off in a huff when the terrain is flat eh?
Our walk ended at some rock pools filed with crystal clear water and a small but picturesque waterfall. Here we were able to take a one hour break to have some lunch and a swim. My cheese and tomato toastie had survived the journey but Vincent’s pitta filled with marinated chicken and sweet chilli sauce had seen better days. The moral of this story is that it is best to take a basic sandwich or toastie with you for lunch because anything else will basically steam up, get soggy and become totally rank.
After lunch, and seeing as we were already wet, we decided to have a paddle about in the water with our clothes on (trainers included). We’d worked up quite a sweat during our humid jungle walk so being able to take a dip in the refreshingly cool water was amazing.
As we were splashing around, we heard a commotion. We turned around to see the guy in army fatigues (and now wearing some swimming shorts) becoming increasingly hysterical as he had discovered a leech in his armpit. His dad asked him to hold still while he removed the offending creature. Cue lots of shouting and some actual tears.
After lunch our guide led us back through the jungle and Deer Cave but our tour wasn’t over yet! Instead, we were taken to Lang Cave, the smallest cave in Mulu National Park and famous for its beautiful and ornate rock formations.
Discovered in 1977 by a local Berawan man named Lang Belarek, Lang Cave showcases the impact of water eroding limestone rock over thousands of years. Rolling waves were sculpted into the ceiling of the cave (for some reason they reminded me of filo pastry on a pie) and in one area the stalactites and stalagmites even resembled jellyfish!
In some areas you could see the process happening (albeit incredibly slowly) before your eyes, as water dripped off stalactites and onto the ground.
Lang Cave is also home to cave worms, which dangle sticky, translucent threads (basically like a spiderweb) from the rock in order to catch small insects. These silken threads looked so delicate and beautiful when they caught the light but I imagine they are pretty deadly for any insect that is unfortunate enough to encounter them.
Like Deer Cave, Lang Cave has a boardwalk and given its small size, our exploration of Lang Cave only took about 30 minutes. Our guide then left us at the Bat Observatory from which we could view the bat exodus. By this point we were kind of sick of being in wet clothes and so we decided to walk back to our room, get showered and changed and grab some dinner. We’d see the bat exodus tomorrow, after all, they have to always come out and search for food don’t they?
This however, is an extremely risky strategy - we didn’t realise that the bat exodus is actually weather dependent (don’t you just love nature?). Later that evening we actually went outside the park HQ and we saw the bat exodus from a distance. The weather was fine and dry and to us it looked like a huge cloud of smoke spiralling across the sky. Very cool!
The walk back from the Bat Observatory is also a great opportunity for more wild-life spotting, even if you don’t have a guide with you. We saw colourful millipedes, scores of butterflies and brightly coloured lizards so make sure to keep your eyes peeled!
Racer Cave and Bat Exodus
Duration: 4 hours (Racer Cave). The bat exodus usually starts after 5pm and basically lasts as long as the bats want to come out of the cave.
The next day we were up bright and early for our first proper adventure caving experience. I decided that I’d wear the same still wet clothes from the day before as I figured I was just going to get dirty anyway (don’t judge me, please). A short boat ride down the river later and we arrived at the entrance to the Racer Cave.
Our guide then gave us our harnesses, helmets and head torches and made sure that we were securely strapped in. After a short safety briefing and an explanation on how to use our equipment, we were ready!
The Racer Cave experience is ideal for anyone who wants to try adventure caving for the first time. We had to climb up ropes, abseil down steep slopes and crawl and squeeze ourselves into narrow passageways, which basically gave us a taste of what a proper caving or ‘spelunking’ experience would be like.
There were moments when I wondered whether I’d really be able to squeeze through a certain gap or pull myself up a sheer edge and then when I did it, the buzz of joy I got was incredible. This is definitely an experience that is worth getting dirty for - by the end I was damp with sweat and my legs and hands were smeared in mud but the physical exertion made me feel exhilarated.
The cave gets its name from the Racer snakes that live in the cave’s nooks and crannies, waiting to pounce on unsuspecting bats and swiftlets. Our guide showed us a small recess where he knew Racer snakes were likely to be and each member of our group went in to see if they could spot them.
When it was our turn, we shone our head torches up to the ledge and they were actually moving, darting in and out as though they were trying to catch something! I’ve only ever seen this in nature documentaries, so to see it happen in real life was…well, one of those bucket list things. (Vincent said they were so active because they thought I was a small, brown bat. Nice.)
You’ve probably already guessed that Racer Snakes aren’t the only occupants of this cave. I actually lost count of the number of hand-sized poisonous spiders the guide pointed out, along with millipedes, scorpions, cockroaches and bats. You definitely need to be careful where you put your hands, because the spiders are seriously huge.
The only light in Racer Cave came from our head torches. There were no proper paths and to my untrained eye, no distinguishing features that would enable me to work out how to get back to the entrance without our guide.
I did ask the guide whether anyone had ever got lost inside this cave and he said it had happened once with a group led by an inexperienced guide. Yikes. I could see how it could happen - everywhere looked the same to me and this was despite the fact that I was wearing a head torch! At one point our guide said that he wanted us to experience the real darkness of the cave and asked us to shut off our torches. It was absolutely pitch black - I couldn’t see Vincent and he was standing next to me! (And normally, I can see that shining white skin anywhere…)
This experience does require you to be reasonably physically fit and to have some upper body strength as you will be pulling yourself up and down ropes quite a lot as well as clambering over rocks. You should also ideally wear shoes with a good grip as it is quite slippery and muddy inside. I could have made a better choice than my 5 year old Nike trainers.
The boat dropped us back to the park HQ around 1pm and after a much needed shower and some lunch, we enjoyed a bit of downtime and a nap before heading out to the Bat Observatory. We actually managed to do a bit more nature spotting near our room - there is literally wildlife everywhere.
What had started off as a bright, sunny day had rapidly changed to a drizzly, grey afternoon. We set off at 3.45pm on the walk to the Bat Observatory, which basically follows the same jungle route as to the Deer Cave, hoping that the spattering sound of rain on the leaves of the trees above us would eventually ease off.
The observatory is basically a small amphitheatre-like area that has been set up for people to watch the bats flying out of Deer Cave. There is a small shop where you can buy some snacks and drinks (including beer) so that you are sufficiently fed and watered while you wait for the bats. It’s basically like a nature cinema.
Whilst the amphitheatre area is at the mercy of the elements, there is also another section that is covered should the heavens open while you wait for the bats to appear. As it was raining when we arrived, we went in here and got some drinks and then had a look at the posters about the different species of bats that live in Deer Cave.
Whilst 12 species of bats live in Deer Cave, the biggest colony are the Wrinkled-Lipped bats whose population is estimated to be between 2.5 and 3.5 million. These little guys aren’t the prettiest but they do look kind of cute - sort of like a tiny squashed pig with wings.
They also have extremely voracious appetites: a single bat will eat 300 or more flying insects each night, with the total number of insects consumed by the bat population running into hundreds of tonnes each year. (This is why you can walk around in the jungle in Mulu without wearing any insect repellant and not be munched to death by mozzies.)
However, being able to see the bat exodus is a hit-and-miss affair. Bats know that there will be fewer insects flying around on rainy days and so, much like myself, they don’t venture out in wet weather. I hear you bats, I really do. Better to have a cup of tea and watch something on Netflix.
Looking up through the drizzle at the grey sky, I wasn’t feeling very hopeful. This was something that I had wanted to see ever since I first saw it on David Attenborough’s Planet Earth but it didn’t seem very likely that they would be out today, especially as they had been out hunting the day before. I was also already having to manage my expectations: when I first heard about the bat exodus I thought bats would be flying around my head, getting caught in my hair and everything. I was kind of looking forward to that. When I got there I realised that it was actually going to take place at quite a distance above us. Yes, I am an idiot, I know.
At about 5.00pm the rain had eased off slightly and so we went to sit outside. Suddenly someone pointed up - against the grey clouds there was a sudden thin wisp of what looked like black smoke, winding its way across the sky. But of course, it wasn’t smoke. It was thousands of bats.
We waited a couple of minutes and then another swarm burst out of the cave, spiralling high into the air and swirling across the sky like a snake. After that a cloud of bats would stream out of the cave every few minutes, corkscrewing into the sky before heading out over the jungle for their nightly hunt. And with each stream of bats there was also a sound: a low, deep whirring of all those tiny wings beating through the air.
And then at about 5.45pm it was as though the remaining bats in Deer Cave, having seen their friends give it the okay, had mustered up the courage to go hunting in the drizzle. For the next 30 minutes we watched an endless stream of bats leave the cave in a thick swarm, weaving across the sky and disappearing into the forest. Alongside the stream were hunting Bat Hawks, flying alongside the millions of bats and waiting to pick off some of the unlucky ones.
By 6.30pm there were a few final stragglers leaving the cave. It was now just us and a handful of people left at the observatory and eventually we started our walk back through the jungle. Both of us were quiet - watching the bat exodus was an amazing experience and we resolved to come back the next night to see it all over again, if nature would let us be so lucky.
As we walked, the sounds of cicadas, crickets and other buzzing insects filled our ears and every now and then a hunting bat flew past our heads. It seemed like I had got my wish after all.
Clearwater Cave and Cave of the Winds
Duration: 4 hours
After two very adventurous days we were ready to take things a bit easier and so we decided to make a visit to the Clearwater and Wind Caves. This didn’t mean that we got a lie-in though!
The day started with a lovely longboat ride along the Melinau River. Whilst you can walk 4km along a nature trail to reach these caves, we felt like we had done plenty of strenuous activity already and so we opted for the boat ride. Plus, a longboat ride is just so much fun - think cool breeze in your hair and lots of stunning scenery.
I mean, where else are you going to get on a longboat and travel down a river in the middle of the jungle? Might as well do it here!
Batu Bungan Market
Our first stop on this tour was a visit to a Penan longhouse and a market at Batu Bungan. Now, it’s usually this type of visit that puts me off going on tours at all: I don’t like being herded around carpet shops or jewellers or spice markets (as a result of bad memories from package holiday excursions, perhaps). However, our guide just left us to wander about as we pleased, which was fine and dandy with me.
At this market people were selling traditional Penan handicrafts (jewellery, woven baskets and mats and blow pipes) and it was quite interesting to see the items being made. You could also try your hand at shooting a traditional blow pipe, if that is your sort of thing.
The market is basically a way of helping Penan people to earn a little income, because sadly their traditional nomadic way of life has been destroyed due to large scale commercial logging and the building of palm oil plantations in Sarawak.
After half an hour at the market we hopped back on the boat and headed off to visit the Cave of the Winds or ‘Wind Cave’ for short. From the boat we walked up a sloping boardwalk and some concrete steps to get to the mouth of this cave. Wind Cave gets its name from the cool breeze that constantly flows through it and which offered a nice relief from the sticky humidity of the jungle outside.
Like Lang Cave, Wind Cave is famous for its intricate and very beautiful cave formations and unique features such as the Sky Garden, where a sink hole in the roof of the cave has allowed enough light in to enable plants to grow around the walls of the cave. As we looked up into the Sky Garden we could see swiftlets entering the cave via the sink hole and watched them swooping around before they headed off into the darkness towards their nests, clicking as they flew.
The piece de resistance of Wind Cave is undoubtedly the King’s Chamber. This cathedral-like room is literally a limestone feast for the eyes, with majestic and ethereal-looking columns and colossal stalactites and stalagmites stretching out as far as the eye could see.
Definitely a room magnificent enough for a King but it’s actually not the rocky splendour that lends this room its name: if you look carefully enough, some of the formations are said to look like a king and his soldiers standing in his chamber.
After an hour in Wind Cave we headed back to the boat again for another short trip down the river to Clearwater Cave. Now, between you and the entrance to the cave are 200 steps but don’t be daunted, just take your time getting up there and you will definitely find Clearwater to be worth the workout!
If you read my intro to Mulu National Park (did ya?) you will already know that Clearwater Cave is massive (current estimates have it at 220km in length, although there are still areas of it that haven’t yet been explored). Only a tiny part of it is actually open to regular visitors - if you want to explore the other sections of the cave further you have to be a qualified adventure caver or sign up to the one of the intermediate or advanced level tours of the cave offered by the park.
Spiky tear-drop shaped rocks covered in bright green plants and shrubbery frame the entrance to Clearwater, with the greenery looking almost lurid in comparison to the grey rock. Interestingly, these single leaf plants known as Monophilia Pendula are indigenous to Clearwater Cave and basically found nowhere else in the world.
When we entered into the darkness of the cave the first thing we noticed was the loud sound of rushing water. The cave was shaped by a subterranean river that still flows through much of it today and is responsible for the beautiful undulating shape of Clearwater.
Once inside, we saw that the area around the underground river was lit up, enabling us to clearly see the way that the river had carved through the rock, leaving behind striated walls that looked very like marble. At some points, the sound of the river was so loud that I could barely hear what our guide was explaining!
Clearwater Cave also seemed to have its own mini ‘Garden of Eden’: in one section, the roof of the cave had fallen through and I could see where a cluster of trees and bushes had grown as close to the edges of the hole as possible, taking advantage of the light available.
Like Lang and Wind Cave, Clearwater has a range of beautiful and unique rock formations: we saw stalagmites that looked like stumpy cactuses and scalloped ridges on the cave ceiling, a reminder of a bygone era when the river flowed through this area of the cave.
One of the most interesting features of the cave were these grey spikes near the entrance that we mistook to be rock: our guide explained that this was in fact bacteria that lived on the cave walls. The bacteria grow towards the light, resulting in a mass of grey pinnacles that look like a sea of skyscrapers in an urban city.
Next door to Clearwater is Lady Cave, a small section with some impressive stalactites and stalagmites. The cave is actually named after a stalagmite that casts a shadow onto the wall that looks eerily like a lady. Just a tiny bit creepy.
Our tour of Clearwater was over and it was now time to tackle the 200 steps back down to river level. If just the thought of climbing down those steps makes you a bit sweaty, fear not, because relief is close at hand. While visitors are not allowed to swim in the river inside Clearwater, you are allowed to go for a cooling swim in a natural lagoon just by the picnic area at the bottom of the cave.
So get your ass down those steps and have a splash around in a real jungle river before you have to take your longboat ride home. Usually the waters here are crystal clear, but heavy rains the evening before had washed sediment into the river, turning it a muddy brown colour (I will admit that this put me off a bit). Still pretty clear though, so if you fancy it, jump straight in!
Mulu Canopy Walk - a chance to get your head in the clouds!
Duration: 2 hours
Anyone who knows me well will know that I have a head for heights. Tall buildings, cliff edges, the slopes of a mountain…you name it, I simply love being at the top of things and ideally at the precipitous edge of them. This isn’t so I can take a ‘crazy’ selfie showing how intrepid I am. Nope, it’s more about the basic rush I get from just being there. A visceral feeling that comes from my bowels (yes, I did just write ‘bowels’), that is a heady mix of fear and excitement.
So, if you are like me, Mulu’s ‘Sky Walk’ is the perfect place for you to be. It’s also a great activity to add on to the end of your trip as it can be done in the morning of your last day before you take a flight out in the afternoon. Simples.
Pro-tip: in the peak season this activity is super popular and sells out quickly, so I would advise booking this in advance, ideally before you arrive. Group sizes are a maximum of 8 people and there are 6 time slots a day starting from 7am-2pm.
We took a short 30 minute stroll along a jungle boardwalk to get to the start of the canopy walkway and even this heralded more unmissable wildlife and insect sightings, plus an up-close encounter with some of the most colossal trees I have ever seen. A perfect photo opportunity to showcase how tiny we really are when compared to the wonders of nature.
The canopy walk at Mulu is one of the longest tree-based canopy walks in the world with 16 hanging bridges suspended 25 metres above the ground across a total length of 480 metres. If these numbers are making your eyes glaze over, let me summarise: it’s basically fucking high.
These bridges, that will definitely wobble and sway as you walk across them, criss-cross over lush tree tops and fast flowing rivers and give you a view of the rainforest that is usually reserved for the monkeys and birds that inhabit it. The walk also gives you a chance to learn about the countless plants and animals that grow and inhabit the ‘understory’ layer of the forest. Beetles, snakes, lizards - they are all there, just under the canopy and you’ll see them if you look hard enough!
We were the last people in our group and so we walked really slowly, savouring the quiet - it was just us and the sounds of the forest. I was in my element! It was a thrilling feeling just to walk across the bridges (and only two people can cross each bridge at a time) and the views of the rainforest canopy, the limestone mountains in the distance and the rivers rushing beneath us were just incredible.
We were SO high up, so high in fact that when we looked down we couldn’t even see the forest floor. Around us the rainforest just seemed to stretch off for miles in all directions: green and endless. I knew that sadly this wasn’t the reality, but on the canopy walkway I got a glimpse into what untouched rainforest might look like.
As we crossed one of the last bridges on the walk and started to climb down the ladder leading to the ground, our guide pointed to the sky. Taking off from one of the trees was a hornbill, the state bird of Sarawak and the national bird of Malaysia. We just about managed to glimpse its brightly coloured bill and dark feathers through the leaves.
Entry Fees and A Chat About Cash Monies
The entrance pass to Mulu National Park costs 30RM for non-Malaysians and is valid for 5 consecutive days. If you want to stay longer, you will have to renew it again. For Malaysians, your entry fee is half price, whoop! Children and Malaysian senior citizens have different entry fees - see this for more details. On top of this cost you will have to pay additional fees for guided tours to all the caves and for the Canopy Walk.
Just to re-iterate, if there is something you really want to do and would be gutted to miss out on, I’d recommend that you book it in advance when you arrive at the Mulu park office or via the national park website.
Here’s a list of the activities we did (pricing accurate as of March 2019):
Night Walk - 22RM (£4) per person
Garden of Eden Valley Walk - 120RM (£22.50) per person
Racer Cave - 165RM (£31) per person
Wind and Clearwater Cave - 67RM (£12.50) per person
Canopy Walk - 45RM (£8.50) per person
Of course the Bat Exodus is free and there are unguided free walks around the park as well. I would highly recommend the Mulu Botanical Heritage Trail.
Other costs to consider:
Wi-fi vouchers can be purchased at the Park HQ and costs 5RM (around £1) for each device and lasts 24 hours. Wi-Fi is sketchy though and the signal is only available at the Mulu Cafe so don’t get it unless you REALLY need it.
If you lose or rip-off the wrist band that the park gives to you at registration, you have to pay 10RM (£2) to replace it. Total rip off, but thems the rules.
How much did our stay cost?
4 nights and 5 days at Mulu National Park cost us 3584RM total (£674) or 1792RM (£337 per person). This included all of our flights (Kuala Lumpur to Miri; Miri to Mulu; and Mulu to Kota Kinabalu); accommodation; meals and snacks and bottles of water; any additional accessories we had to buy and all of our guided activities. Considering everything we did, I think this is great value for money. Remember, you can always make your stay considerably cheaper by staying outside of the national park and by booking your flights in advance.
Our experience at Mulu was unforgettable: it felt like we were given a key to a hidden underground world. The scenery, adrenaline rush experiences, caves and wildlife more than made up for the fact that we spent most days being either damp or totally piss-wet through - a state of affairs that I would ordinarily hate! But in Mulu, none of that mattered and we finished everyday simply feeling happy, excited and invigorated. I would go back in a heartbeat.
Have you been to Mulu? Got any recommendations about caves in other countries we should visit? We’d love to hear your thoughts so hit us up in the comment section below!