Sierra Leone officially the Republic of Sierra Leone, is a country in West Africa that is bordered by Guinea to the northeast, Liberia to the southeast, and the Atlantic Ocean to the southwest. Sierra Leone is a constitutional republic with a directly elected president and a unicameral legislature. The country has a tropical climate, with a diverse environment ranging from savannah to rainforests. The country covers a total area of 71,740 km2 (27,699 sq mi)[5] and with an estimated population of 6 million (2011 United Nations estimate)