Gunung Mulu National Park

1 Introduction
2.1 Equipment
2.2 Guides
2.3 Tourist information
2.4 Best time to visit
3 Background
4 Flora and fauna
5 Gunung Mulu
6 Treks from Camp 5
7 Melinau Gorge
8 The Pinnacles
9 Gunung Api (Fire Mountain)
10 Clearwater Cave
11 Deer Cave
12 Lang's Cave
13 The Sarawak Chamber

Tucked in behind Brunei, this 529 sq km park lays claim to Gunung Mulu, which at 2376 m is the second highest mountain in Sarawak, and the biggest limestone cave system in the world. Mulu is basically a huge hollow mountain range, covered in 180-million-year-old rainforest. Its primary jungle contains an astonishing biological diversity. The park was awarded UNESCO World Heritage status in 2000.

Just outside the national park boundary on the Tutoh River there are rapids which it is possible to shoot; this can be arranged through tour agencies.

Ins and outs


A small store at the Park HQ sells basic necessities; there is also a small shop just outside the park boundary, at Long Pala. A sleeping bag is essential for Gunung Mulu trips; other useful items include a good insect repellent, wet weather gear and a powerful torch.


No visitors are permitted to enter the caves without an authorized guide; guides can be arranged from Park HQ or booked in advance from the national parks office in Miri. There are some treks around the park that can be done without a guide. Most of the Mulu Park guides are very well informed about flora and fauna, geology and tribal customs. Tour agencies organize guides as part of their fee.

Tourist information

For up-to-date information on Mulu, see For cavers wishing to explore caves not open to the public (those open to visitors are known as 'show' caves), there are designated 'adventure caves' within an hour of Park HQ. Experienced cave guides can be organized from headquarters. The most
accessible adventure cave is the one-hour trek following the river course through
Clearwater Cave
. Cavers should bring their own equipment. Tougher caves such as the Sarawak Chamber can only be visited by advanced cavers who have some experience. The Park Manager needs to approve this trip.

Best time to visit

It is best to avoid visiting the park during school and public holidays.


In Robin Hanbury-Tenison's book
The Rain Forest
, he says of Mulu: “All sense of time and direction is lost.” Every scientific expedition that has visited Mulu's forests has encountered plant and animal species unknown to science. In 1990, five years after it was officially opened to the public, the park was handling an average of 400 visitors a month. Numbers have increased markedly since then - the area is now attracting more than 12,000 tourists a year - and as the eco-tourism industry has extended its foothold, local tribespeople have been drawn into confrontation with the authorities. In the early 1990s, a series of sabotage incidents was blamed on the Berawan tribe, who claim the caves and the surrounding jungle are a sacred site.

In 1974, three years after Mulu was gazetted as a national park, the first of a succession of joint expeditions led by the British Royal Geographical Society (RGS) and the Sarawak government began to make the discoveries that put Mulu on the map. In 1980 a cave passage over 50 km long was surveyed for the first time. Since then, a further 137 km of passages have been discovered. Altogether 27 major caves have now been found speleologists believe they may represent a tiny fraction of what is actually there. The world's biggest cave, the
Sarawak Chamber
, was not discovered until 1984.

The first attempt on Gunung Mulu was made by Spencer St John, the British consul in Brunei, in 1856 . His efforts were thwarted by “limestone cliffs, dense jungle and sharp pinnacles of rock”. Dr Charles Hose, Resident of Marudi, led a 25-day expedition to Gunung Mulu in 1893, but also found his path blocked by 600-m-high cliffs. Nearly 50 years later, in 1932, a Berawan rhinoceros hunter called Tama Nilong guided Edward Shackleton's Oxford University expedition to the summit. One of the young Oxford undergraduates on that expedition was Tom Harrisson, who later made the Niah archaeological discoveries. Tama Nilong, the hunter from Long Terawan, had previously reached the main southwest ridge of Mulu while tracking a rhinoceros.

The cliffs of the Melinau Gorge rise a sheer 600 m, and are the highest limestone rock faces between north Thailand and Papua New Guinea. The limestone massifs of Gunung Api and Gunung Benarat were originally at the same elevation as Gunung Mulu, but their limestone outcrops were more prone to erosion than the Mulu's sandstone. Northwest of the gorge lies a large, undisturbed alluvial plain which is rich in flora and fauna. Penan tribespeople are permitted to maintain their lifestyle of fishing, hunting and gathering in the park. At no small expense, the Malaysian government has encouraged them to settle at a purpose-built longhouse at
Batu Bungan
, just a few minutes upriver from the
Park HQ, but its efforts have met with limited success because of the desire of many
Penan to maintain their travelling lifestyle. Penan shelters can often be found by riverbanks.

Reeling from international criticism, the Sarawak state government set aside 66,000 ha of rainforest as what it called 'biosphere', a reserve where indigenous people could practise their traditional lifestyle. Part of this lies within the park. In Baram and Limbang districts, the remaining 300 Penan will have a reserve in which they can continue their nomadic way of life. A further 23,000 ha has reportedly been set aside for 'semi-nomadic' Penan.

In 1961 geologist Dr G Wilford first surveyed Deer Cave and parts of the Cave of the Winds. But Mulu's biggest subterranean secrets were not revealed until the 1980s.

Flora and fauna

In the 1960s and 1970s, botanical expeditions were beginning to shed more light on the Mulu area's flora and fauna: 100 new plant species were discovered between 1960 and 1973 alone. Mulu Park encompasses an area of diverse altitudes and soil types - it includes all the forest types found in Borneo except mangrove. About 20,000 animal species have been recorded in Mulu Park, as well as 3500 plant species and 8000 varieties of fungi (more
than 100 of these are endemic to the Mulu area). Mulu's ecological statistics are astounding: it is home to 1500 species of flowering plant, 170 species of orchid and 109 varieties of palm. More than 280 butterfly species have been recorded. Within the park boundaries, 262 species of bird (including all eight varieties of hornbill), 67 mammalian species, 50 species of reptile and 75 amphibian species have been recorde

Mulu's caves contain an unusual array of flora and fauna too. There are three species of swiftlet, 12 species of bat and nine species of fish, including the cave flying fish (
Nemaaramis everetti
) and blind catfish (
Silurus furnessi
). Cave scorpions (
Chaerilus chapmani
) - which are poisonous but not deadly - are not uncommon. Other subterranean species include albino crabs, huntsman spiders, cave crickets, centipedes and snakes (which dine on swiftlets and bats). These creatures have been described as “living fossils... [which are] isolated survivors of ancient groups long since disappeared from Southeast Asia.”

Gunung Mulu

The minimum time to allow for the climb is four days, three nights; tents are not required if you stay at Camps 1 and 2. The main summit route starts from the plankwalk at Park HQ heading towards Deer Cave. The Mulu walkway forks left after about 1 km. From the headquarters it is an easy four- to five-hour trek to Camp 1 at 150 m, where there is a shelter, built by the RGS/Sarawak government expedition in 1978. The second day is a long uphill slog (eight to 10 hours) to Camp 4 (1800 m), where there is also a shelter. Past Camp 3, the trail climbs steeply up Bukit Tumau, which affords good views over the park, and above which the last wild rhinoceros in Sarawak was shot in the mid-1940s. There are many pitcher plants (
Nepenthes lowii
) along this stretch of trail. From Camp 4, known as 'The Summit Camp', the path passes the helicopter pad, from where there are magnificent views of Gunung Benarat, the Melinau Gorge and Gunung Api. The final haul to the summit is steep; there are fixed ropes. Around the summit area, the
Nepenthes muluensis
pitcher plant is common - it is endemic to Mulu. From Camp 4 it takes 1½ hours to reach the summit, and a further seven hours back down the mountain to Camp 1.

Camps 1, 3 and 4 have water (providing the tank has been filled by rain water). Water should be boiled before drinking. It is necessary to bring your own food; in the rainy season it is wise to bring a gas cooking stove. A sleeping bag and waterproofs are also necessary and spare clothes, wrapped in a plastic bag, are a good idea.

Treks from Camp 5

For a three-day trip, it is necessary to take a longboat. It takes two to three hours, depending on the river level, from Park HQ to Kuala Berar; it is then a two- to three-hour trek (8 km) to Camp 5. Visitors to the Camp 5 area are also advised to plan their itinerary carefully as it is necessary to calculate how much food will be required and to carry it up there. There is a fairly well-equipped shelter with kitchen, bathrooms with shower and communal sleeping space which can house a maximum of 50 people. The camp is next to the Melinau River; river water should be boiled before drinking. There is a solar power generator to power radios, pump river water and for low lighting after dark.

Camp 5 is located in the Melinau Gorge, facing Gunung Benarat, about four to six hours upstream from the Park HQ. From the camp it is possible to trek up the gorge as well as to the Pinnacles on Gunung Api. It is advisable to hire a longboat for the duration of your time at and around Camp 5. The boat has to be abandoned at Kuala Berar, at the confluence of the Melinau and Berar rivers. It is only used for the first and last hours of the trip, but in the event of an emergency, there are no trails leading back to the Park HQ and there are stories of fever-stricken people being stuck in the jungle.

Melinau Gorge

Camp 5 nestles at the end of the gorge, across a fast-flowing section of the Melinau River and opposite the unclimbed 1580-m Gunung Benarat's stark, sheer limestone cliffs. The steep limestone ridges, which lead eventually to Gunung Api, comprise the east wall of the gorge. Heading out from Camp 5, the trail fizzles out after a few minutes. It takes an arduous two to three hours of endless river crossings and scrambles to reach a narrow chute of whitewater, under which is a large, deep and clear jungle pool with a convenient sandbank and plenty of large boulders to perch on. Alfred Russel Wallace's
Troides brookiana
- the majestic Rajah Brooke's birdwing - is particularly common at this little oasis, deep in undisturbed jungle. The walk involves criss-crossing through waist-deep, fast-flowing water and over stones that have been smoothed to a high polish over centuries: strong shoes are recommended as is a walking stick. Only occasionally in the walk upstream is it possible to glimpse the towering 600 m cliffs. Mulu can also be climbed from the south ridge of Melinau Gorge; it is three hours to Camp 1, five hours to Camp 3, a steep four- to five-hour climb to Camp 4, and finally two hours to the top.

The Pinnacles

The Pinnacles are a forest of sharp limestone needles three-quarters of the way up Gunung Api. Some of the pinnacles rise above treetops to heights of 45 m. The trail leaves from Camp 5, at the base of the Melinau Gorge. It is a very steep climb all the way and a maximum time of three to four hours is allowed to reach the pinnacles (1200 m); otherwise you must return. There is no source of water en route. It is not possible to reach Gunung Api from the Pinnacles. It is strongly recommended that climbers wear gloves as well as long-sleeved shirts, trousers and strong boots to protect themselves against cuts from the razor-sharp rocks. Explorers on Spenser St John's expedition to Mulu in 1856 were cut to shreds on the Pinnacles: “three of our men had already been sent back with severe wounds, whilst several of those left were much injured,” he wrote, concluding that it was “the world's most nightmarish surface to travel over”.

Gunung Api (Fire Mountain)

The vegetation is so dry at the summit that it is often set ablaze by lightning in the dry season. The story goes that the fires were so big that locals once thought the mountains were volcanoes. Some of the fires could be seen as far away as the Brunei coast. The summit trek takes a minimum of three days. At 1710 m, it is the tallest limestone outcrop in Borneo and, other than Gunung Benarat (on the other side of the gorge), it is probably the most difficult mountain to climb in Borneo. Many attempts to climb it ended in failure; two Berawans from Long Terawan finally made it to the top in 1978, one of them the grandson of Tama Nilong, the rhinoceros-hunter who had climbed Gunung Mulu in 1932. It is impossible to proceed upwards beyond the Pinnacles.

From Camp 5, cross the Melinau River and head down the
Limbang Trail
towards Lubang Cina. Less than 30 minutes down the trail, fork left along a new trail which leads along a ridge to the south of Gunung Benarat. Climbing higher, after about 40 minutes, the trail passes into an area of leached sandy soils called
(heath) forest. This little patch of thinner jungle is a tangle of many varieties of pitcher plants.

It is possible to trek from Camp 5 to
, although it is easier to do it the other way .

Clearwater Cave

This part of the Clearwater System, on a small tributary of the Melinau River, is 107 km long. The cave passage - 75 km of which has been explored - links Clearwater Cave (Gua Ayer Jernih) with the
Cave of the Winds
(Lubang Angin), to the south. It was discovered in 1988. Clearwater is named after the jungle pool at the foot of the steps leading up to the cave mouth, where the longboats moor. Two species of monophytes - single-leafed plants - grow in the sunlight at the mouth of the cave. They only grow on limestone. A lighting system has been installed down the path to
Young Lady's Cave
, which ends in a 60-m-deep pothole.

On the cave walls are some helictites - coral-like lateral formations - and, even more dramatic, are the photokarsts, tiny needles of rock, all pointing towards the light. These are formed in much the same way as their monstrous cousins, the Pinnacles, by vegetation (in this case algae), eating into and eroding the softer rock, leaving sharp points of harder rock which 'grow' at about 0.5 mm a year. Inside Clearwater you can hire a rowing boat and follow the river for 1.5 km upstream, although the current is strong.

Clearwater can be reached by a 30-minute longboat ride from the Park HQ (RM27 per person). Individual travellers must charter a boat for a return trip. Tour agents build the cost of this trip into their package, which works out considerably cheaper. There are daily scheduled guided tours of the cave.

Deer Cave

This is another of Mulu's record breakers: it has the world's biggest cave mouth and the biggest cave passage, which is 2.2 km long and 220 m high at its highest point. Before its inclusion in the park, the cave had been a well-known hunting ground for deer attracted to t
he pools of salty water running off the guano. The silhouettes of some of the cave's limestone formations have been creatively interpreted; notably the profile of Abraham Lincoln. Adam's and Eve's Showers, at the east end of the cave, are hollow stalactites; water pressure increases when it rains. This darker section at the east end of Deer Cave is the preferred habitat of t
he naked bat. Albino earwigs live on the bats' oily skin and regularly drop off. The cave's east entrance opens onto 'The Garden of Eden' - a luxuriant patch of jungle, which was once part of the cave system until the roof collapsed. This separated Deer Cave and Green Cave, which lies adjacent to the east mouth; it's open only to caving expeditions.

The west end of the cave is home to several million wrinkle-lipped and horseshoe bats. Hundreds of thousands of these bats pour out of the cave at dusk. Bat hawks can often be seen swooping in for spectacular kills. The helipad, about 500 m south of the cave mouth, provides excellent vantage points. VIPs' helicopters, arriving for the show, are said to have disturbed the bats in recent years. From the analysis of the tonnes of saline bat guano, scientists conclude that they make an 80-km dash to the coast for meals of insects washed down with seawater. Cave cockroaches eat the guano, ensuring that the cavern does not become choked with what locals call 'black snow'.

Lang's Cave

Part of the same hollow mountain as Deer Cave, Lang's Cave is less well known but its formations are more beautiful and it contains impressive curtain stalactites and intricate coral-like helictites. The cave is well lit and protected by bus-stop-style plastic tunnels.

The Sarawak Chamber

Discovered in 1984, this chamber is 600 m long, 450 m wide and 100 m high - big enough, it is said, to accommodate 40 jumbo jets wing-tip to wing-tip and eight nose-to-tail. It is the largest natural chamber in the world. It is now possible for cavers with some experience to visit the cave, with the approval of the Park Manager. It is a three-hour trek to the cave following the summit trail. Access to the cave is through Gua Nasib Bagus, following a river trail bordered by 50-m-high sheer rock faces on both sides for 800 m. After a further scramble, cavers reach the dark mouth of the chamber. It is not permitted to enter any further as it is considered too dangerous.

This is edited copy from Footprint Handbooks. For comprehensive details (incl address, tel no, directions, opening times and prices) please refer to book or individual chapter PDF
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