The Metropolitan Cathedral of Buenos Aires, located in the neighborhood of San Nicolás, is the main catholic temple in Argentina. It was founded in 1580 by Juan de Garay and has undergone several reconstructions due to structural problems and poor materials.

Initially, it was a modest church of adobe and wood, demolished in 1605. In 1618, a new church was built, which was soon replaced due to its small size. In 1620, the diocese of Buenos Aires was created, and its first cathedral was an inadequate construction. In 1671, a new cathedral with three naves and a tower was completed, but the poor quality of the materials led to its deterioration.

In 1722, the Cabildo Eclesiastico took charge of repairs, managing to finish the cathedral in 1725. However, in 1752, part of this cathedral collapsed, and in 1753 the construction of the current cathedral began under the supervision of the architect Antonio Masella. The new cathedral, with a Latin cross design, three naves and six chapels, progressed slowly due to economic difficulties, but was inaugurated in 1791.

The neoclassical façade, with 12 columns symbolizing the Apostles, was completed in 1823. In 1856, the Ecclesiastical Curia was built. The cathedral was declared a historical monument in 1942 and intensively restored between 1994 and 1999. In 2013, a museum dedicated to Pope Francis, former archbishop of Buenos Aires, was inaugurated.

The interior of the cathedral is remarkable for its mix of styles and grandeur, with five naves, a 41-meter-high dome and a Venetian mosaic floor. It houses the mausoleum of General San Martin and several frescoes and sculptures. The main facade is inspired by the Bourbon Palace in Paris, and in its atrium is the "Cota 0", the leveling point of the city. The cathedral also contains a mural in memory of the victims of the Holocaust and of attacks in Argentina.