Banjarmasin or Bandjarmasin (both: bänˌjərmäˈsĭn) [key], city (1990 pop. 481,371), capital of Kalimantan Seletan prov., S Borneo (Kalimantan), Indonesia, on a delta island near the junction of the Barito and Martapura rivers. An important deepwater port, it is the trade center of the rich Barito basin; exports include rubber, pepper, timber, oil, coal, gold, and diamonds. There is a large oil refinery, and coal mines and sawmills are in the vicinity. In the 14th cent. Banjarmasin was part of the Hindu kingdom of Madjapahit, but it passed to Muslim rulers in the late 15th cent. The Dutch opened trade there in 1606. The British controlled the city for several brief periods, and in 1787 it became a Dutch protectorate. There is much flooding, and many of the inhabitants live on raftlike dwellings. A state university is in the town.