Countries the Congo River Flows Through

The Congo River—the world's second-largest by discharge and ninth-longest—drains a vast basin of about 3.7 million km² across Central Africa. The river system (main stem and major tributaries) touches nine countries:

• Democratic Republic of the Congo (DRC) – the vast majority of the basin and the river's entire lower course
• Republic of the Congo – the lower river forms part of the border and flows through the capital, Brazzaville
• Central African Republic – northern tributaries (Ubangi, etc.)
• Cameroon – far northwestern tributaries
• Zambia – headwaters of the Chambeshi River, the Congo's ultimate source
• Angola – southwestern tributaries; Cabinda exclave at the river's mouth
• Rwanda – eastern headwaters (Nyabarongo/Rukarara)
• Burundi – southernmost headwaters (Ruvyironza)
• Tanzania – eastern shore of Lake Tanganyika, which drains into the Congo via the Lukuga River

Note: The river's main stem flows almost entirely within the DRC, crossing the equator twice. The basin's transboundary nature makes cooperative water management (via the International Commission of the Congo-Oubangui-Sangha Basin, CICOS) essential for sustainable development.