Petrópolis, also known as the Imperial City, is a municipality in the Southeast Region of Brazil. It is located in the state of Rio de Janeiro, 68 kilometres northeast of the city of Rio de Janeiro. According to the 2022 Brazilian census, Petrópolis municipality had a population of 278,881 inhabitants. Besides being the largest and most populous city in the Fluminense Mountain Region, the city also has the largest GDP and HDI in the region.