If you like to go trekking in the jungle and explore impressive caves, you should visit Mulu National Park in Sarawak, Borneo. The national park, also called Gunung Mulu, is an UNESCO World Heritage site and covering 529km² of jungle. It’s the largest national park in Sarawak. The park is known for the karst (limestone) formations and the spectacular caves. Mulu is located 100km east of Brunei. Explore the jungles in Borneo by visiting Mulu National Park in Malaysia.

A very short history

Mulu is 40 million years old, the sandstone and limestone peaks of Mulu are even older, around 60 million years. The massive limestone formation was formed deep under the sea. The limestone was uplifted and two peeaks were created: Mount Api and Mount Benarat. Water dissolves limestone and as a result large caves were created. The rainforests in Borneo make sure there is enough water to develop underground lakes, rivers and caves. The third peak is Mount Mulu and is made of sandstone.

In 1978 a large multi- disciplinary expedition was send to Mulu by the Royal Geographical Society. The expedition lastest 15 months and they explored around 60 km of caves. Over the years scientists explored over 300km of the caves. Millions of bats and swiflets live inside the caves. Researches recorded 28 species of bats in the caves and in the park (not all species live inside a cave). Three caves are open to visitors, the Lang Cave, Deer Cave and the Clearwater Cave.

Activities

All activities in Gunung Mulu are organised by a licensed guide of the Sarawak Forestry. The tours booked via the park office are cheaper but you need to book in advance. Tour agencies charge more but are your only option if the tours of the park office are fully booked.

Deer & Lang Cave

The guided tour to the Deer and Lang cave begin at HQ. It starts with a 3km walk on a wooden plankway to the bat observatory. The Deer cave is a large cave with many passages and is inhabited by 3 million Wrinkle Lipped Bats. Swiflets live here too but are more difficult to see as they live in the high ceilings. On the way back your guide takes you to the Lang cave.

The Lang cave is a relative small cave with stalagmites and stalactites. The cave is inhabited by bats and because of the smaller size it’s easier to spot bats in the Lang cave. After visiting the caves you can admire (if you are lucky) the bat exodus. Millions of bats leave the cave after 17.00pm to find food. The bats don’t fly out when it’s raining. They eat more than they need and can live without food for a few days. They hypernate for a few days or a week if necessary.

Clearwater Cave

The guided tour starts at HQ with a longboat ride on the Melinau river. The first stop is at Penan longhouse and market at Batu Bungan. You can support the local village by buying a small souvenir. The Clearwater cave is one of the largest caves in the world and approximately 230km in length. Inside the Clearwater cave is a river. The erosion process of the underground rivers and lakes inside the caves takes millions of years. You are not allowed to swim inside the cave. Outside at the picknick deck you are allowed to swim. The water is crystal clear and you are swimming in the middle of the rainforest.

Pinnacle climb

The climb to the Pinnacles is a high risk activity. The duration of the tour is three days and two nights. You start with a boat ride on the Melinau River. The tour starts with a visit to the Clearwater cave (optional). If you don’t want to visit you have to wait for the others. Afterwards the tour goes to Kuala Litut. Here you start the 9km trek to Camp 5. It’s a basic forest shelter and accommodation is limited. Sleeping mats are provided but bedsheets and towels are not. There is a clear water spot at Camp 5 where you can swim and relax in the cool waters.

The second day the trek starts at 6am. The trail is 2,5km but the viewpoint is 1200 meters higher. During the last part you have to climb on ladders and hold on to ropes. The descent is even more challenging and takes around 5 hours. The Pinnacle tour is a challenging climb, it is not a hiking trek. Keep in mind your capabilities and limitations. Visitors did get injured because they underestimated there fitness level or their fear of heights.

What to bring when visiting Mulu?

• Raincoat or poncho
• Insect repellent
• Anti-slip walking/ hiking shoes
• Flashlight
• Day- backpack
• Water: make sure you bring enough water when going on a tour, at least 2 liters. The rainforest is hot and humid and even I drank 2,5 – 3 liters per day.
• Swimming gear: if you are going to visit the Clearwater cave
• Your permit to enter Mulu
• Bring your own food. Most tours do not include lunch.
• Sunscreen: apply sunscreen and let it dry before using insect repellent
• Cap, headwrap or scarf to protect your head against the sun
• Some patience to spot animals

Mulu is a rainforest so one very important item to bring is a raincoat or poncho. Another essential item is mosquito or insect repellent. Don’t use too much repellent. The scent is a warning to animals that you are around and makes it more difficult to see them. Watching wildlife, birds and the bat exodus requires some patience. I tried to see the bat exodus twice and without any luck. The bats can live without food for a few days. Both days I went it was raining and even bats don’t like rain. I can’t blame them!

Responsible travel

When you are visiting Mulu National Park do not leave anything behind. Take your empty bottles and packaging with you and throw it away at your guesthouse or at HQ. You are allowed to bring your own food but please do not leave food behind for the monkeys or birds to eat. The animals are more likely to get sick. You are not helping them by giving them food.

Are you interested to know more about sustainable travel. Read other articles about tips to fly greener and how to travel more sustainable.

Accommodation

There a few options for accommodation. You can stay at bungalows and lodges around HQ at Mulu World Heritage Area Accommodation. Check availability and prices at Mulu Park. There is one 5-star hotel, Mulu Marriott. A more cultural option is to stay at Mulu Village. There are several guesthouses and homestays available. The guesthouses in the village are pretty basic but a great way to meet and talk to locals.

How to get to Mulu?

Mulu National Park is only reachable by flight. You can fly from Miri, Kota Kinabalu and Kuching. The only airline available is MAS Wings. It’s possible to book the flight via Malaysia Airlines as well. Book the flights as soon as possible. Flights tend to be fully booked a few weeks in advance. From Mulu Airport you can walk to your guest house or arrange a pick up at your accommodation. The Marriott hotel is a bit further out. They have a shuttle service to and from the airport and the entrance of the National Park.

In the worlds jungle travel

Visit other National Parks in Borneo. Find ancient cave paintings at Niah National park or go hiking for a few days and try to spot the proboscis monkey at Bako National park. Borneo is also an excellent destination to go snorkelling and diving. Visit Kota Kinabalu or go further north to Sabah and admire the white sandy beaches, crystal clear waters and spot the gorgeous colourful fish. See what Borneo looks like and go for a virtual picture tour of Malaysian Borneo.

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