Buraco do Lume, Historical square in Centro, Rio de Janeiro, Brazil

Buraco do Lume is a square in downtown Rio de Janeiro situated between major streets, opening up in a frame of buildings from different periods. The space has clear pathways where pedestrians move daily, surrounded by a mix of older and newer structures from the city's development.

The square was formerly Praça Henrique Lage, demolished in 1963 to serve as the construction site for the Edifício Lúcio Costa, headquarters of the Banco do Estado da Guanabara. In 1973 the bank auctioned the land to Grupo Lume, which planned a 50-storey tower, then Brazil's tallest; works halted after partner Banco Halles was liquidated in April 1974. Grupo Lume was liquidated on 23 April 1976, leaving an abandoned excavation that people nicknamed Buraco do Lume.

The nickname "Buraco do Lume" comes from the abandoned construction site of Grupo Lume, whose planned 50-story headquarters left a large excavated hole after the company was liquidated in 1976. The square is a traditional site for political demonstrations: PT militants gather on Mondays and PSOL on Fridays. It was renamed Praça Mário Lago in honor of the lawyer, poet, radio host, lyricist and actor.

The square lies in downtown Rio de Janeiro, close to Largo da Carioca and its metro station, so it is reached on foot from the station exits. It is a public area open at any hour, with the Monumento Leonístico at one end and the Marielle Franco statue nearby. On Mondays PT militants gather here and on Fridays PSOL militants do.

The nickname "Buraco do Lume" comes from Grupo Lume, which bought the lot at auction in February 1973 for 111 million cruzeiros to build a 50-storey headquarters, then went bankrupt in April 1976, leaving an excavated foundation hole. The square was renamed Praça Mário Lago in 2009, when the new street sign was finally installed under Mayor Eduardo Paes.