Largest island of the Riau archipelago in the South China Sea, Indonesia; area 1,075 sq km/ 415 sq mi. Bintan is Indonesia’s main bauxite producer. The low-lying, often marshy island also produces timber, rubber, tin, pepper, and gambier (a woody vine whose leaves are used in tanning). The main town and port is Tanjung Penang. There is an airfield in the north.