It is the oldest square in Buenos Aires. Its location was determined in the 2nd foundation of the city, in 1580. It is surrounded by historical and governmental buildings, such as the Cabildo, the Cathedral, the Casa Rosada (National Government seat), the Palace of the Government of Buenos Aires, banks, and ministries.
The "Pirámide de Mayo" is on the center of the square, it is a monument that has the shape of an obelisk, and it was built in 1811 to celebrate the first anniversary of the revolution. In 1856 it was completely refurbished by artist and architect Prilidiano Pueyrredón. Its height is of 19 meters.
Bolívar, H. Yrigoyen, Balcarce and Rivadavia streets border it, Downtown
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Subways: Line A, Plaza de Mayo Station; Line D, Catedral Station; Line E, Bolívar Station.