The Basilica of San Francisco, was built in Baroque style between 1879 and 1885 and declared a National Historic Monument in 1986. Many of the attendees of the Congress of 1816 were accommodated here, during which  Argentina declared independence, and it also served as a refuge for troops of two great military generals: Manuel Belgrano and San Martín.

At the main entrance to the Church one can see elaborate ironwork and the dome coated with white, green and blue tiles.
Inside several historical artifacts are stored, such as the table where the Declaration of Independence was signed and the first National Flag hoisted in Tucumán, on the 8th of October, 1814. A must-see is the high altar which was made by indigenous missions emphasizing the pillars covered in gold leaf.

Attached to the temple is the Convento de San Francisco (not open to the public) which was built in 1902 on Jesuit temple foundations. Currently, the convent consists of a central courtyard surrounded by trees and alleries. Formerly, many underground tunnels ran from this site, connecting the church with different points of the city.