The Plaza de Mayo is the oldest public square in Buenos aires, and has been the scene of many of the most important events in the city's history, from the second founding of the city in 1580, through the revolution of independence, to more recent political demonstrations. The square is named after the Argentine revolution, which began on May 25, 1810. Around the square are several important buildings: the Cabildo, the Metropolitan Cathedral, where Pope Francis conducted mass for 20 years, the Casa Rosada, seat of the national government, the national revenue office (AFIP), the national bank and the intelligence secretariat. https://turismo.buenosaires.gob.ar/en/otros-establecimientos/plaza-de-mayo

Dominating the Plaza de Mayo, the Casa Rosada - or pink house - is the seat of the Argentine national government and houses the president's office. Witness to much of the city's history, it was from the balconies of the Casa Rosada that Juan and “Evita” Perón addressed the masses during the late 1940s and early 1950s. The central archway was designed by Italian architect Francisco Tamburini, who was also responsible for the original design of the Colón Theatre, and was completed in 1890. https://turismo.buenosaires.gob.ar/en/otros-establecimientos/casa-rosada