Lake Cohoha and Lake Rugwero lie in Rwanda's southeast, partly extending into Burundi. There are also eight sizable lakes that lie entirely within Rwanda: Lakes Rwehikama, Ihema, Muhazi, Mugesera, Hago, and Rwanye in the east, and Lakes Ruhondo and Burera in the north.
Most of Rwanda's rivers are in the eastern part of the country. The Kagera River in the east forms the boundary with Tanzania and part of the boundary with Burundi. With a total length of 692 kilometers (430 miles), the Kagera is the longest river in Rwanda. The Nyabarongo River and its tributaries drain much of the Central Plateau.
In the west, the Ruzizi flows southward from Lake Kivu along the border with the Democratic Republic of the Congo, into Burundi, and on to Lake Tanganyika. In the south, the Luhwa and Akanyaru Rivers form parts of the boundary with Burundi.