The parochial church of Agüero is an interesting building initiated in the heat of century XI. It is dedicated to Saint Saviour and it was initiated in plant with a single nave and an apse but it was finished in gothic style with the lateral naves and a pointed door.

At the present time, there is a peculiar vestibule where the entrance to the crypt which belongs to the century XVII can be seen. The crypt was turned in a parochial Museum. In the interior of the church, next to baroque altarpieces, there is the greatest altarpiece which has a stature (probably of century XVI), a peculiar romanesque stairs of snail and a precious organ of the century XVIII.

In the modern age, throughout centuries XVI and XVII, the town of Agüero sees increased its parochial treasure. Of century XV it was already a reliquary safekeeping, piece of special interest because is crowned with a Crucifix and it has a detachable viril.

In century XVI it arrives to Agüero a precious complete game of different clothes that priests usually use, all them with an enormous value. All these pieces show the shield of arms of the donor: Francisco Aznárez, a man who was manager of the parish of Agüero between 1.527 and 1.560 and then he became in a canon of Jaca, city in which he died in 1.562. Of century XVII they are left two things: a parochial cross of sobregilded silver whose base it has a circular base and a deposit for oils in candelabrum form. Several choir books complete the treasure of the parish and a romanesque Virgin, possibly of century XIII.

The tympanum of this church belongs to the century XI and it is of great value. This tympanum is romanesque and it is presided by the Maiestas Domini - Christ in Majesty- escorted by the symbols of the four evangelists or "Tetramorfos".