Cameroon, republic in western Africa, bounded on the north by Lake Chad; on the east by Chad and the Central African Republic; on the south by the Republic of the Congo, Gabon, and Equatorial Guinea; and on the west by the Bight of Biafra and Nigeria. The nation is shaped like an elongated triangle, and forms a bridge between western Africa and central Africa. The nation has a total area of 475,442 sq km (183,569 sq mi). Yaoundé is the capital, and Douala is the largest city.