The country is divided into four main regions: the Basse-Coté lowlands, populated mainly by the Susu ethnic group; the cooler, mountainous Fouta Djallon that run roughly north-south through the middle of the country, populated by Fulas, the Sahelian Haute-Guinea to the northeast, populated by Malinké, and the forested jungle regions in the southeast, with several ethnic groups. Guinea's mountains are the source for the Niger, the Gambia, and Senegal Rivers, as well as the numerous rivers flowing to the sea on the west side of the range in Sierra Leone and Ivory Coast.
The highest point in Guinea is Mount Nimba at 1,750 m (5,740 ft). Although the Guinean and Ivorian sides of the Nimba Massif are a UNESCO Strict Nature Reserve, the portion of the so-called Guinean Backbone continues into Liberia, where it has been mined for decades; the damage is quite evident in the Nzérékoré Region at 7°32′17″N 8°29′50″W.