Baixada Fluminense

The Baixada Fluminense, located in Rio de Janeiro state, Brazil, is a region situated on Guanabara Bay between Rio de Janeiro to the south and the Serra dos Órgãos hills to the north. Part of the Rio de Janeiro Metropolitan Region, it has a population of around three million, making it the second most populous area in the state after Rio itself. Its municipalities include Duque de Caxias, Nova Iguaçu, São João de Meriti, Nilópolis, Belford Roxo, Queimados, Mesquita, Magé, Guapimirim, Japeri, Paracambi, and Seropédica.

Historically, the region was known as Baixada da Guanabara until the 19th century. In the 18th century, it served as a key transport route for gold from Minas Gerais. During the 19th century, it became one of Brazil's first coffee plantation regions but faced economic decline under Emperor Pedro II due to railroads reducing river and road traffic.

In the 20th century, the area experienced significant migration, particularly from Espírito Santo, Minas Gerais, and Northeastern Brazil, as people sought better living conditions near Rio de Janeiro. However, by the second half of the century, it was known for poverty, crime, and inadequate social services, with favelas present in the region. Marsh drainage projects were initiated to improve sanitation.

In 2005, a mass shooting occurred in which 29 people were killed during an operation led by military police forces.