Baram River, river in northwestern Borneo. Rising in the Iran Mountains, it flows 250 miles (400 km) west and northwest, mostly through primary rain forest to the South China Sea at Baram Point. Above the lowest 100 miles, gorges and rapids make upstream navigation difficult. The Baram is Sarawakâs second longest river; its tributaries include the Bakong, Apoh, Palutan, and Patah.