Porto Alegre is the capital and largest city in the Brazilian state of Rio Grande do Sul. The city population is 1,509,939 inhabitants (2010), the tenth most populous city in the country and the centre of Brazil's fourth largest metropolitan area, with 4,405,760 inhabitants (2010). The city is the southernmost capital city of a Brazilian state. Porto Alegre is one of the top cultural, political and economic centers of Brazil. Two Mercosul countries, Argentina and Uruguay, border on the State of Rio Grande do Sul.