The Temple of Nuestra Señora de la Expectación or Potosina Cathedral, is located where the initial Parish of San Luis existed, being its first Parish Priest Don Andres Nieto who administered the sacraments from May 1593. In 1670 this parish church was demolished and the construction of a new temple was begun, being the Master Architect Nicolas Sanchez, and it was blessed in 1730.
Of baroque style and built with lime and singing, it has three naves, the central one composed by eight vaults and the two lateral ones by seven, in its facade there were the carved apostles in quarry that at the same time were replaced by the ones brought from Turin in Carrara marble by the Bishop Montes de Oca, which are placed in ornate niches. The central body of its façade is decorated with rich baroque and Solomonic columns.
The interior is embellished by Claudio Molina and Giuseppe Compiani (this decorator of some palaces in Constantinople, Russia, Alexandria and California). The marble mausoleums of Carrara and stucco were also ordered by Bishop Montes de Oca to protect his remains and those of his predecessors.
The high altar is made up of a beautiful masonry cypress: it has two sections: on the first, the demonstrator, and on the top, the image of Our Lady of Expectation, the work of Perrusky. Opposite the cypress tree is the altar table, and below it, a beautiful sculpture of Saint Sebastian. It is a copy of the one that exists in the Catacombs of San Sebastián, in Rome, whose author is Giorgetti, a disciple of Bernini. His Excellency Montes de Oca brought this sculpture from Rome, carved by a disciple of Antonio Canova, at a price of $10,000.00.
In the sacristy there are several paintings such as the death of Saint Joseph, the Seven Sacraments, by Paez, Saint Dominic, Lord of the Column, Saint Nicholas of Bari, by Nicolas Rodriguez Juarez, Saint Rose, by Patricio Morlete, an oil painting representing Father Ambrosio Rivera de Pereda, who directed the works for the transformation of the Cathedral. Among the oil portraits of the bishops, the one of His Excellency Mr. Montes de Oca, by the Italian Erulo Eroli, stands out.