The parish church of Santa Cruz de la Serós is the last vestige of the old convent founded at the end of the 10th century by Sancho Garcés II Abarca and by his wife Urraca Fernandez. It enjoyed moments of great splendour, principally during the reign of Ramiro I. After the Council of Trent (1543-1563) religious communities were obliged to move from rural areas to towns and cities, This is how the Benedictine order settled in Jaca, where it remains to this day.

Of the initial monastic complex only the church and the tower remain. The building has a single nave, covered with a barrel vault, with two supporting arches. The eastern end is closed by a semicircular apse. On either side of the chancel there are two chapels with cross-vaulted ceilings from which two small apses develop, giving the whole floorplan of the building the appearance of a Latin cross.

Over the section before the chancel there is a second floor reached via a staircase hidden inside the north wall. The doorway at the western end consists of an arch with two architraves between which runs a line of spherical balls, of which the central one represents a human head. The tympanum presents a monogram of Christ flanked by two lions, a simpler version of the composition of the tympanum on the western door of the cathedral in Jaca.

Within the ring of the monogram of Christ is the following motto in latin:”I am the doorway, pass through me ye faithful. I am the spring of life: you have greater thirst of me than of wine, ye who enter this well-met temple to the Virgin” And under the paws of the lions an inscription reads: “Repent so you may invoke the name of Christ”.

The artistic decoration is simple. The former main altarpiece of the temple is in the chapel on the northern side. It is a Gothic piece that dates from 1490. The altarpiece is covered by a dustsheet. In the central niche there is an image of the Virgin and Child in polychrome alabaster, also from the end of the 15th century. In the chapel on the southern side there are two altarpieces, one of which is presided over by a canvas of St Geronimo, dated 1618, while the other, dedicated to the saints Voto and Felix is from the 18th century.