Benin is a long narrow north-south strip of land in West Africa located between the Equator and the Tropic of Cancer. It is bounded by Togo to the west, Burkina Faso and Niger to the north, Nigeria to the east and the Bight of Benin and South Atlantic to the south. Benin, with an area of 112,622 km², is one of the smallest countries of Africa. The Niger River defines the northern border with Niger. The country is divided into four geographical areas. From the low lying coastal plain the terrain passes northward into a low plateau incised by north to south flowing rivers and then plains with scattered hills that seldom reach 400m and finally a range of mountains in the northwest border with Togo with the highest point of 658m. 


The geology of Benin is composed of two sub-parallel domains – an extensive northern region comprising Proterozoic age crystalline rocks of the Dahomeyide Orogen divided into a series of NNE trending belts and a southern region of late Phanerozoic sedimentary rocks ranging from Cretaceous to Recent in age. Alluvial sediments of Neogene age cover the northeastern part of the country along the border with Niger.