Caseros Prison, Former detention center in Parque Patricios, Buenos Aires, Argentina

Caseros Prison was a 22-story concrete building in Parque Patricios, Buenos Aires, with an H-shaped footprint and over 1,500 cells measuring 1.2 by 2.3 meters. Each cell held a bed, toilet, table and chair fixed to the floor. The design prevented direct sunlight from reaching prisoners.

The National Commission of Penitentiary Constructions planned the prison in 1960 under Arturo Frondizi, but the project was abandoned three years later after a Federal Penitentiary Service report called it inhumane. Work resumed in 1969 under Juan Carlos Onganía, and the prison opened on 23 April 1979 under Jorge Rafael Videla. It closed in 2001; its two towers were demolished between 2004 and 2007.

The prison's name comes from the avenue it faces, Caseros. After it closed in 2001, the site served as a film set: much of the miniseries Tumberos was shot there in 2002, and El Marginal was filmed between 2016 and 2019. The old 1877 building on the same grounds is planned to become a cultural centre.

The site is now abandoned and not open for visits, so viewing it from outside is the only option. Its location in Parque Patricios is reachable by public transport, though the neighborhood is less central and requires some orientation.

The prison's H-shaped plan and 22-storey height were meant to keep all sunlight from the cells. In the 1980s and 1990s, inmates knocked holes through the outer walls to reach daylight and talk with relatives in the street below. Notes and small objects travelled on ropes woven from mattress fibres, a setup the prisoners called palomas, "pigeons".