Liberia (full name, Republic of Liberia) covers an area of approximately 99,000 sq km with a terrain consisting of mostly flat to rolling coastal plains rising to rolling plateau and low mountains in the northeast. Liberia borders Guinea, Cote d'Ivoire and Sierra Leone, and has 579 km of coastline. The country is divided into 15 counties: Bomi, Bong, Gbarpolu, Grand Bassa, Grand Cape Mount, Grand Gedeh, Grand Kru, Lofa, Margibi, Maryland, Montserrado, Nimba, River Cess, River Gee and Sinoe. Monrovia is the capital, with a time zone corresponding to that of GMT. The currency is the Liberian dollar, and exports include diamonds, iron ore, rubber, timber, coffee and cocoa. The population of approximately 3,400,000 people are mostly African and include Kpelle, Bassa, Gio, Kru, Grebo, Mano, Krahn, Gola, Gbandi, Loma, Kissi, Vai, Dei, Bella, Mandingo and Mende ethnic groups. Primary languages are English and various African languages, and the predominant religions are Christianity, Islam and indigenous beliefs.