Which square is the main foundational square of Buenos Aires?

Plaza de Mayo is the main foundational square of Buenos Aires. It occupies the historic centre of Argentina’s capital and has been a stage for major political, civic, and national events since the city’s colonial beginnings.

Its origins reach back to Juan de Garay’s refounding of Buenos Aires in 1580, when a central plaza was planned for the settlement. For much of the colonial period, the area was divided into two spaces: the Plaza Mayor and the Plaza de Armas, later known as the Plaza de la Victoria and Plaza del Fuerte.

The modern square was created in 1884 when the Recova Vieja colonnade separating those spaces was demolished. Its name commemorates the May Revolution of 1810, the beginning of the process that led to Argentine independence. The May Pyramid, inaugurated in 1811, is Buenos Aires’ oldest national monument.

The square is surrounded by landmarks including the Casa Rosada, the Cabildo, and the Metropolitan Cathedral. It is also associated with the Mothers of the Plaza de Mayo, whose weekly demonstrations made it an enduring symbol of public remembrance and protest.