Impor­tant both for its high bio­di­ver­si­ty and for its karst fea­tures, Gunung Mulu Nation­al Park, on the island of Bor­neo in the State of Sarawak, is the most stud­ied trop­i­cal karst area in the world. The 52,864-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 not­ed. The park is dom­i­nat­ed by Gunung Mulu, a 2,377 m‑high sand­stone pin­na­cle. At least 295 km of explored caves pro­vide a spec­tac­u­lar sight and are home to mil­lions of cave swiftlets and bats. The Sarawak Cham­ber, 600 m by 415 m and 80 m high, is the largest known cave cham­ber in the world.