It was Madrid’s main cathedral until the completion of the work done on the Almudena Cathedral. Its high altar contains the tomb of San Isidro, the patron saint of the city.

 The church was planned by the Jesuit Pedro Sánchez in 1620, following the Gesú de Roma church model. In 1769, Ventura Rodríguez planned a new presbytery and the high altarpiece. It was temporarily classified as a cathedral when the Madrid-Alcalá diocese was created in 1885. In 1992 it changed classifications, when it was consecrated as the The Almudena Cathedral.

With a Latin cross floor plan, it has one nave, side chapels, with the cross being the most notable aspect, and the top is flat. The chapels alternate square and rectangular shapes, and they are mutually connected. The treatment of the inner space creates great visual value, both in the structure and rhythm of the chapels and galleries, where the linteled and half-point openings are combined, and in the rich decoration done by Ventura Rodríguez in the 18th Century. The front has a certain civil and palatial touch. On its top, there are two unfinished square towers.

 In 1936 it was set on fire. The destruction of the covers was almost complete and the central dome collapsed, being rebuilt and restored after the Civil War by Javier Barroso, who also managed to carry out the completion of the unfinished towers at the same time.