Fula Rapids, rapids on the Baḥr al-Jabal (Mountain Nile), about 4 miles (6.5 km) below Nimule, South Sudan. A large island divides the river, the eastern channel of which carries most of the water. At the island’s southern end, the river enters the 2-mile- (3.2-km-) long stretch of rapids with a drop of about 20 feet (6 metres). It then rushes through a narrow gorge more than 300 feet (90 metres) long, falls into a deep cavity less than 40 feet (12 metres) across, and passes over rapids that extend beyond the northern end of the island.