Location: 225, Bolivar St. Montserrat
It was the largest Jesuit temple and today is the oldest church in Buenos Aires. The temple still maintains elements from the 17th. Century in its structure. Behind the baroque façade there are images, paintings and furniture inside from the 18th. Century.
Construction began in 1686, on top of the adobe walls of an earlier temple that stood there. The temple was finished in 1675, dedicated to the Saint Founder of the Order.
After 1712 it was refurbished by Juan Kraus keeping the existing façade and towers. In the work helped the Jesuits Bianchi, Wolff, Weger and Prímoli.
It was consecrated in 1734 and it was the City Cathedral between 1775 and 1791 after the Jesuits had been expelled. Became a military barracks during the resistance against the British invasion in 1806.During 1816 and 1820 important open chapters (Cabildos Abiertos) and meetings were held here. A university was created in 1821. In 1955 the temple was set on fire intentionally during social riots.