Sierra Leone, officially the Republic of Sierra Leone is a country in West Africa. It is bounded on the north by Guinea, Liberia, in the southeast and the Atlantic Ocean in the south and west. It covers a total area of 71,740 km ² and has an estimated population of 6,296,803 inhabitants. The country has a tropical climate with a diverse environment ranging from savannah to rainforests. The republic's capital of Freetown, the seat of government, the main economic center and largest city, with approximately 1.1 million inhabitants. It is the country with the third lowest in the HDI ranking.