Gunung Mulu National Park, situated in the Malaysian State of Sarawak on the island of Borneo, is outstanding both for its high biodiversity and for its karst features. The park is dominated by Gunung Mulu, a 2,376 m-high sandstone pinnacle and the property is the most studied tropical karst area in the world. The geological Melinau Formation contains a remarkable concentration of caves, revealing a geological history of over more than 1.5 million years. High in endemism, Gunung Mulu National Park provides significant natural habitat for a wide range of plant and animal species, both above and below ground. The 52,865 ha park contains seventeen vegetation zones, exhibiting some 3,500 species of vascular plants. Its palm species are exceptionally rich, with 109 species in twenty genera recorded, making it one of the worlds richest sites for palm species. Providing protection for a substantial area of Borneo’s primary tropical forest and a home for a high diversity of species, including many endemics and threatened species, the large cave passages and chambers provide a major wildlife spectacle in terms of millions of cave swiftlets and bats