Nilópolis (Portuguese pronunciation: [ˈnjilɔpʊˈʎiʃ]) is a municipality in Brazil, located in the Rio de Janeiro state's southwestern region, bordering São João de Meriti, Mesquita and Rio de Janeiro. It is the smallest municipality in Rio de Janeiro state, with a total area of 19.39 km². The population of 157,483 inhabitants living in an area of 9 km² and the remaining area corresponds to the Gericinó's Natural Park. Officially, the population density exceeds 8,120 inhabitants/km², but if calculated just 9 km² occupied, it becomes the most densely populated city in Brazil with more than 17.400 inhabitants/km². Currently, São João de Meriti has the highest population density, with 12,897 inhabitants/km².