The Ruvubu at its confluence with Nyabarongo. The Ruvubu comes from the left, the Nayabarongo from the right; the confluent Kagera heads north.
The Ruvubu River (also spelt Ruvubu and Ruvuvu) is a river in central Africa whose waters gather from the most distant portion of the Nilebasin. It is about 300 km long. It rises in the north of Burundi, near the town of Kayanza and then does a southward arc through Burundi, being joined by the Ruvyironza River near Gitega. From there it runs northeast, through the Ruvubu National Park, up to the Tanzanian border. After a stretch along the border, the Ruvubu crosses properly into Tanzania, before joining the Nyabarongo River on the Tanzania–Rwanda border near Rusumo Falls, to form the Kagera River.