Mount Bisoke, Active volcano in the Virunga Mountains, Rwanda

Mount Bisoke is an active stratovolcano on the Rwanda–Democratic Republic of the Congo border, its summit in Rwanda at 3,711 metres. The cone is symmetrical, built of trachyandesitic lava, and crowned by a crater lake 450 metres across. Its steep slopes carry equatorial rainforest and alpine meadows, and an alignment of scoria cones runs from its foot to the northeast.

The volcano experienced two major eruptions, in 1891 and 1957. The second event created two smaller cones on the mountain's northern flank.

The name Bisoke also appears as Visoke, Bisoko, Kirunga Visoke and Wissoke. The summit crater holds a lake 450 metres across, and the mountain is one of the Virunga peaks whose slopes give habitat to the endangered mountain gorilla, with the Karisoke Research Center founded by Dian Fossey in the valley to the west.

Visitors can reach the mountain through two hiking trails. The main route takes about six hours round trip, and permits are required.

The Karisoke Research Center founded by Dian Fossey lies in the valley west of Bisoke, not on its slopes. The volcano itself holds two crater lakes, one of them the largest in the Virunga range, and its 1957 eruption opened two small cones on the north flank, 11 km from the summit.