Good Luck Cave

Gua Nasib Bagus - Sarawak Chamber

Useful Information

Location: Gunung Mulu National Park, island of Borneo, Sarawak. 3-4 h walk from the Park headquarters through the jungle. (3°57' N, 114°47' E)
Open: Sarawak Chamber Overnight At Camp 1: All year daily after appointment.
Fee: Sarawak Chamber Overnight At Camp 1: Per Person MYR 310.
Classification: SpeleologyKarst cave
Light: none
Dimension: L=2,900 m, VR=412 m.
Sarawak Chamber: L=641 m, W=429 m, H=113 m, Ar=162,700 m², V=9,670,000 m³.
Guided tours: full day cave trekking tours, L=4,000 m. Min=3, Max=6, MinAge=16.
Photography: allowed
Accessibility: no
Bibliography: Jeanne K Hanson (2007): Caves, 142 pp, 16 colour and 30 B&W photos. Chelsea House, New York.
pp 43-54 Lubang Nasib Bagus and the Sarawak Chamber of Borneo.
Address: Gunung Mulu National Park, Borsarmulu Park Management Sdn Bhd, No 11, Pekan Mulu, Mulu, 98070, Sarawak, Tel: +6085-792-600/601/602/603, Fax: +6085-792-605. E-mail:
As far as we know this information was accurate when it was published (see years in brackets), but may have changed since then.
Please check rates and details directly with the companies in question if you need more recent info.


1980 discovered during the British-Malaysian Mulu ’80 Expedition.
2011 chamber laser scanned.


This cave contains the worlds largest natural underground chamber. Lubang Nasib Bagus or better known as Sarawak Chamber is 641 m long, 429 m wide and 113 m high. The exact size of this chamber was not easy to determine, as a caver needs an hour to cross it, and it took many years to completely explore it. Sarawak Chamber is only one room of this huge cavern. The whole passage has an enormous size, as do many caves at this Park.

Headlamps are not able to light more than a tiny spot of the big hall, some photographs made with special equipment showed nevertheless only parts of the chamber. They were made using special magnesium flashes, which is actually antique technology. Magnesium is a metal which oxidizes with a bright flame. In the first half of the 20th century flash bulbs were actually bulbs filled with magnesium wool. An electric current fired them and they burned down inside the bulb. As a result they could be used only once. They were replaced by electronic flashes which have an electric bulb which does not burn down. It works as long as there is enough energy in the battery. The flashes used for this chamber were special heavy duty magnesia flashes, huge glass bulbs filled with an enormous amount of magnesium, custom made for such extreme situations. The pictures of Jerry Wooldridge are a milestone of cave photography.

The mouth of the cavern is the resurgence of a stream. Visitors follow the stream upwards, until they reach the cave. The stream normally springs 50 m below the cave entrance, through the debris of a collapsed cave entrance. The cavers climb up to a collapsed part of the roof, then descend back to the river. Inside the cave, the cavers follow the stream upstream to Sarawak Chamber.

Despite its size - or because of its size - the visit to the cave is not really difficult. But as most of the time the passage is filled with water, the ability to swim and appropriate clothes are essential. Because of the high temperature the trip is despite the water not very hard. But its a lot to walk, from the headquarter to the cave entrance its a walk of about 4 hours. Often this trip is done with an overnight stay in a base camp on hour from the cave.

The cave was discovered by Hans Friederich during the British-Malaysian Mulu ’80 Expedition. He was coming down the Melinau Paku Valley on his way back from monitoring an experiment in the Hidden Valley. He found the resurgence cave by following the river upstream to the source. In a first exploration Andy Eavis and others surveyed the main passage. Another team of cavers including Dave Checkley, Andy Eavis, Danny Lawi, and Tony White continued the survey. They were unaware if it was a chamber or a huge passage, and were not able to survey it completely on this trip. They realized that it was actually by far the biggest chamber in the world when they drew up the survey the following day. Many more trips were necessary. The chamber was surveyed by classical means, by laser scanner and much more. Today even a detailed 3D computer model exists which was created in 2011. The Mulu 3D Laser scanning team was awarded the annual Arthur Butcher prize for excellence in Cave Surveying at the British Caving Association annual conference held in Monmouth September 2011.