Monument

The Cabildo of Buenos Aires (Spanish: Cabildo de Buenos Aires) is the public building in the city of Buenos Aires, Argentina, that was used as a seat of the town council during the colonial era and the government house of the Viceroyalty of the Río de la Plata. The building was also seat of other institutions such as the Royal Audience of Buenos Aires, the highest court for appeal of second instance in the territory, operated from April 6, 1661 to January 23, 1812, when it was replaced by an Appeals Chamber. On September 13, 1810, the Primera Junta created the Public Library of Buenos Aires, being the Cabildo its first location for two years. The institution that was housed for the longest in the building was the Buenos Aires prison, from 1608 to 1877, when the prisoners were transferred to the new National Penitentiary on Las Heras Street, when it was inaugurated. The Cabildo was declared National Historic Monument in 1933 and was opened to public as a museum in 1938.