Deer Cave is located near Miri, Sarawak, Malaysian Borneo and is a show cave attraction of Gunung Mulu National Park. It was surveyed in 1961 by G.E. Wilford, of the Malaysian Geological Survey, who predicted that Mulu would yield many more caves in the future (Wilford, 1964). The cave, which is also known as Gua Payau or Gua Rusa by the local Penan and Berawan people, is said to have received its name because of the deer that come to the cave to lick salt-bearing rocks (Tsen, 1993) and shelter themselves.
The cave was surveyed for the first time in the year 1978, producing measurements of 174 m wide and 122 m high in one section that passed through the mountain for a distance of one kilometer. Subsequently a next survey increased the acknowledged passage length to 4.1 kilometers and connected Lang Cave, another show cave within the park, to the Deer Cave System. This survey made in 2009 by the Hoffman Institute of Western Kentucky University revealed the maximum cross sectional area to be in the large southern passage. This was documented at 169 m wide with a ceiling height of 125 m. The northern passage registered the greatest ceiling height at 148m with a cross sectional width of 142 m. The main entrance of Deer Cave was measured at 146 m.
An explanation of the cave's formation is strongly interconnected with the geological history of the island of Borneo itself. Between 40,000,000 B.C. and 20,000,000 B.C., a 1500 m thick layer of sedimentary rocks known as limestone, composed largely of compressed sea shells, developed in lagoons created by coral reefs. The movement of the Asian and Australian tectonic plates caused the crust to buckle and elevate the land once more, giving birth to the island of Borneo and the Mulu mountains, around 5,000,000 B.C. Since then, the landscape was hacked by constant erosion from precipitations and winds. The mountain’s surface is composed mostly of limestone, which dissolves when in contact with fresh-water, and thus has been slowly sculpted into a karst. Rainwater also infiltrates the porous sedimentary rocks after going through the soil and progressively dissolves the limestone, widening the pores and cracks and creating caves of impressive dimensions such as the Deer Cave. This natural process, which is still working, will cause the cave to widen even more in the future.
Access and tourism
Tourism access to the cave (and to the entire park) was opened in 1984. The landscape attracts around 25,000 visitors from countries all over the world every year.
To access Deer Cave, one must first enter the Gunung Mulu National Park, by way of the nearby city of Miri. Malaysian Airlines operates flights of approximately 45 minutes from Miri to Mulu. The park can also be reached by boat from Marudi, but a special booking must be made since no regular boat covers that area.
You can access the Deer Cave by following a three kilometer plank walk, which passes through various places like a swamp, limestone outcrops, etc. This walk is considered an additional attraction to visitors as it takes them through the rainforest (of about 55,000 ha) and by an ancient Penan Burial Cave.
The interior of the cave is lit, but flashlights are recommended for personal use in darker areas.
There is also an area of the cave known as the Garden of Eden, named as such due to rich green vegetation made possible by a hole in the roof providing a small amount of sunlight. Visitor attention may also be drawn to a specific formation which bears a distinct resemblance to the profile of Abraham Lincoln.
In 2008, Prince Albert II of Monaco visited the Gunung Mulu National Park to launch a new camera system as part of the Bat Observatory, which is located near the entrance of the Deer Cave. Known as the Bat Cam, the surveillance technology allows visitors and scientists to observe the millions of bats (over 30 species) that live inside the Deer Cave without affecting their habitat or habits, providing a valuable tool for the study of cave fauna.
The Deer Cave derives its name from an uncommon species of deer, native to Malaysia, which make their home largely in the immediate area of the cave. Additionally, many other animals such as the rhinoceros hornbill, bearded pig, sun bear, and gibbon are native to the local area.
Deer Cave was known as the largest cave passage in the world until the discovery of Sơn Đoòng cave in Phong Nha-Kẻ Bàng National Park in Vietnam. It is part of the Gunung Mulu National Park, a UNESCO World Heritage Site characterized by amazing caves and karst formations in a mountainous equatorial rainforest setting. There are numerous other caves around the Deer Cave, but only three are well-known and open to the public: the Clearwater, Wind and Lang caves.
The Clearwater cave, with approximately 60 kilometers of known passages, is considered the longest cave system in Southeast Asia. It is recognized for its clear underground stream, popular with tourists. The Wind cave is located on the same trail leading to Clearwater cave, and is known for its blowing wind. It contains a chamber dubbed King’s Room, a cavern containing huge columns of stone on both the ceiling and the floor. The Lang cave is the smallest of the caves open to the public. However, its size allows up-close opportunities to see some of the common cave inhabitants such as bats and swiftlets.
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