At 94,919 square miles (245,857 km²), Guinea is roughly the size of the United Kingdom and slightly smaller than the U.S. state of Oregon. There are 200 miles (320 km) of coastline. The total land border is 2,112 miles (3,399 km). The country is bound by Guinea-Bissau to the northwest, Senegal and Mali to the north, the Ivory Coast to the east, Sierra Leone and Liberia to the south and the Atlantic Ocean to the southwest .Guinea is divided into four main regions: the Basse-Cote lowlands in the west along the coast, populated mainly by the Susu ethnic group; the cooler, mountainous Fouta Djalon that run roughly north-south through the middle of the country, populated by Peuls, the Sahelian Haute-Guinea to the northeast, populated by Malinkes, 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 Mont Nimba at 5,748 feet (1,752 m). 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.