Why does the Niger River matter to Benin’s northern border?

The Niger River is significant to Benin’s northern border because it serves as a physical boundary, forming part of the frontier between Benin and the country of Niger.1

Geographically, Benin is a narrow country that extends approximately 420 miles (675 kilometers) northward from the Gulf of Guinea to reach this river. Additionally, the river and its tributaries—specifically the Mékrou, Alibori, and Sota—are essential to the country's hydrology, as they drain the northeastern region of Benin.12