|The park is dominated by the sandstone mass of Gunung Mulu, which stands at 2376m, but the highlight of a journey to the park is the exploration of its awesome caves. Of the four that are open to the public, The Deer Cave is reputed to be the largest cave passage in the world. Millions of bats live in the cave by day, and they time-share it with the swiftlets who occupy it at night. Every night at about 1800 hrs an amazing spectacle occurs as the bats fly out of the cave in a solid convoy, and the swiftlets try to enter. Bat hawks circle round the cave entrance to feast on the emerging bats.|
Lang's Cave is the smallest of the four, but the most beautiful, with colourful stalactites, stalagmites and strange rock formations. The Clearwater Cave has an underground river, and a maze of tunnels. The Cave of the Winds has a chamber of stalagmites resembling a throne and human shapes. All four caves have steps, paths and boardwalks to allow visitors to explore in safety.