4. Salvador, Brazil
Salvador, also known as São Salvador da Bahia de Todos os Santos is the capital of the Brazilian state of Bahia. With 2.9 million people, it is the largest city proper in the Northeast Region and the 4th-largest city proper in the country, after São Paulo, Rio de Janeiro and Brasília. Founded by the Portuguese in 1549 as the first capital of Brazil, Salvador is one of the oldest colonial cities in the Americas.