El Cabildo, a modest, two-story colonial building along the edge of Plaza de Mayo, once served as Buenos Aires’s original city hall. Within the white facade, meetings were held about Argentina’s declaration of independence in the first decades of the nineteenth century, the Uruguayan constitution was signed within the building in 1830, and it housed the National Court of Justice during the late 1800s.
Today, Cabildo is one of the few colonial structures still standing in Buenos Aires. The facade now houses a small museum showcasing paintings, furniture, antiques and costumes from the colonial period. The windows of the building offer some of the best views of the historic plaza just outside.
Plan your visit to Cabildo near the top of the hour to see the changing of the guards ceremony staged out front. On Thursday and Friday afternoons, a craft market is held in the back patio of the building.