Borneo an island in the Malay Archipelago of Southeast Asia. It lies in the Greater Sunda group of islands about 300 miles (480 km) east of Singapore. Surrounding the island are the waters of the Java, South China, Sulu, and Celebes seas and Makassar Strait. Borneo is the third largest island in the world, following Greenland and New Guinea. Its area is about 290,000 square miles (751,000 km2), roughly twice that of Montana. Politically, the island is divided between Indonesia, Malaysia, and Brunei:
Kalimantan is part of Indonesia. Area: about 210.-000 square miles (544,000 km2). Population (2000): 11,331,558. Sarawak is part of Malaysia. Area: 48,050 square miles (124,450 km2). Population (2000): 2,603,485. Sabah is part of Malaysia. Area: 28,460 square miles (73,711 km2). Population (2000): 1,736,902. Brunei is an independent sultanate. Area: 2,226 square miles (5,765 km2). Population (2001): 332,844.
Borneo is an extension of the Asian mainland; only shallow seas separate it from the Malay Peninsula and from the adjacent islands of Sumatra and Java. The interior of the island is predominantly mountainous, with peaks up to about 8,000 feet (2,400 m). Mount Kinabalu (13,455,feet [4,101 m]), in the extreme north near the coast, is the island's highestvpeak. The coast is a low, largely marshy belt, 10 to 50 miles (16 to 80 km) wide, which contains large areas of mangrove swamp.
Borneo lies on the Equator and has a tropically hot and humid climate along the coast. Here temperatures remain fairly constant throughout the year and average about 80° F. (27° C.). The mountainous areas have a cooler climate. Annual rainfall averages from 100 to 160 inches (2,540 to 4,060 mm). Most of the rain falls during two monsoon seasons.
Tropical rain forests, with numerous vines, flowering plants, and dense undergrowth, cover most of Borneo. Among the many animals are elephants, rhinoceroses, small leopards, bears, orangutans, gibbons, and wild pigs. The proboscis monkey is native only to Borneo. Snakes include pythons and cobras. There are many species of birds.