Brasília (Portuguese pronunciation: [bɾɐˈzilɪɐ]) is the federal capital of Brazil and the seat of government of the Federal District. Administratively the city is located in the Federal District, which is in the Central-West Region. Physically it is located in the Brazilian Highlands. It has a population of about 2,562,963 (3,716,996 in the metropolitan area) as of the 2008 IBGE estimate, making it the fourth largest city in Brazil. However, as a metropolitan area, it ranks lower at sixth. It is listed as a UNESCO World Heritage Site. Brasilia is the largest city in the world that did not exist at the beginning of the 20th century.