Gua Payau

Deer Cave - Gua Rusa

Useful Information

Location: Gunung Mulu National Park, island of Borneo, Sarawak. 3 km walk from the National Park office. (3°57' N, 114°47' E)
Open: Lang and Deer Cave: All year daily 14, 14:30.
Fee: Lang and Deer Cave: Per Person MYR 35.
Classification: SpeleologyKarst cave
Light: LightIncandescent Electric Light System
Dimension: L=4,100 m. H=120 m, W=152 m.
Guided tours: L=9 km, D=3 h plus bat exodus.
Deer Cave: L=800 m.
Lang Cave: L=100 m.
V=25,000/a [2019]
Photography: allowed
Accessibility: no
Bibliography: Hans P Hazebroek, Abang Kashim bin Abang Morshidi (2002): A Guide to the Gunung Mulu National Park, A world heritage site in Sarawak, Malaysian Borneo. with a foreword by Dato Sri Abang Haji Abdul Rahman Zohari bin Tun Abang Haji Openg, Minister of Tourism 2002. 91 pp numerous colour photos. SB
L.S. Hall (1996): Observations on bats in Gua Payau (Deer Cave), Gunung Mulu National Park, Sarawak., Sarawak Mus. J. No. 71. 111-124
G.E. Wilford (1964): The Geology of Sarawak and Sabah Caves, Geological Survey, Borneo Region, Malaysia, 1964.
Brook D, A.C. Waltham (1978): The Underworld of Mulu, part 1, Caving International Magazine 1-1978 p3ff.
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.


1961 first survey by G.E. Wilford of the Malaysian Geological Survey.
1978 surveyed by a Royal Geographical Society expedition.
1984 cave opened to the public.
2008 visited by Prince Albert II of Monaco to launch a new camera system as part of the Bat Observatory.
2009 exploration by the Western Kentucky University.


Deer Cave is said to have the highest cave entrance in the world, 100 m wide and 120 m high. It is often compared with St. Paul's Cathedral, we have no idea why, which fits in 5 times over. The cave behind the entrance is a huge passage, nearly the same size, dimly lit by the daylight from the entrance. Deer Cave is a through cave, with two huge entrances. The rock formation at one opening resembles the profile of Abraham Lincoln. The opening is 148 m high and 90 m wide. The other opening is known as the Garden of Eden entrance, because it is surrounded by lush jungle. Actually Garden of Eden is a huge sinkhole, with a diameter of 1 km and surrounded by 150 m to 300 m high limestone cliffs. It qualifies as a KarstTiankeng. There are unique shower head formations named Adam and Eve’s showers spouting columns of water 30 m to the riverbed below. This entrance is 140 m wide and 120 m high. The normal tour ends here and returns on the same trail to the other entrance. But there is a special Garden of Eden-Tour which follows the cave river into the sinkhole.

Actually the cave was, for a long time, the largest cave passage of the world, but only the second largest cave entrance in the world. In 2009 a British team of cavers explored a cave in Vietnam named CaveHang Son Doong, which is now the largest known cave passage and so Deer Cave is number two in both respects. However, the cave has a comparable width and height to Hang Son Dong, but it is only 2 km long while the other is almost 6 km long. And it is actually a show cave and does not require a three day expedition. It has the largest cave portal for a show cave and the 4th largest cave portal at all [2021].

Numerous bats live in the cave, at some parts the cave floor is covered with enormous amounts of bat guano. It is estimated that the cave contains more than three million bats and is said to be the world's largest bat colony. 12 different species are known from Deer Cave, the most frequent is the free-tail or wrinkle-lipped bat (Chaerephon plicata). The others are cave nectar bat (Eonycteris spelaea), greater sheath-tailed bat (Emballonura alecto), Bornean horseshoe bat (Rhinolophus borneensis), Philippine horseshoe bat (Rhinolophus philippinensis), Cantor’s roundleaf bat (Hipposideros galeritus), Fawn roundleaf bat (Hipposideros cervinus), Dayak roundleaf bat (Hipposideros dyacorum), diadem roundleaf bat (Hipposideros diadema), lesser tail-less roundleaf bat (Coelops robinsoni), lesser bentwing bat (Miniopterus australis), and naked bat (Cheiromeles torquatus). The cave also contains a large number of swiftlets which roost in the cave. Both bats and swiftlets use ledges in the rock face high above the ground where they are safe from predators.

In the evening the bats leave the cave in large groups. Like in other bat caves the exodus of the bats in the evenings are a special attraction of this cave. However, they only fly in great numbers if there is no rain, because the raindrops makes their echo location unreliable. And as there are frequent afternoon rains, the chance to see a great number of bats is limited. Each bat eats about 5g to 10g of insects every night, on a good night the bats in Deer Cave eat 30 tons of insects. Obviously the byproduct are huge amounts of bat guano. The guano also creates a smell of ammonia, which is a real drawback. Fortunately the passage is huge and the through cave allows a rapid exchange of the cave air. And finally there is a complex eco system on the ground which feeds on the bat guano, mostly insects, but also predators which hunt those insects. If a bat or a swiftlet falls to the ground it is doomed.

The cave has electric light but it is also lighted by daylight from the entrances, and it has well developed paths. It is reached from the visitor center on a 3 km long wooden raised plank walk. The guided tour includes both Deer and Lang cave. The Bat Exodus begins at 17 and ends around 18 every evening. It is free and you can walk self guided to the bat observatory. But the cave tour is timed to end with the bat exodus. Bring raincoat, sturdy walking shoes, insect repellent, a torch, and some food and drinking water. Torches are recommended for personal use in darker areas and for the walk back after the bat exodus.