The monastery of San Lorenzo de Trasouto, now known as the pazo of San Lorenzo, is a complex of buildings of monastic origin.
As bishop of Zamora, Martín Arias, around the year 1200, and seeing that the time had come for him to retire, he decided to look for a quiet place in Galicia, his native land. This is how he decided to construct the first buildings around 1216, in the area outside the city walls, including the church of San Lorenzo de Trasouto. All this happened before 1216, the year in which a letter of confirmation was issued by King Alfonso IX regarding what was then the church of San Lorenzo de Trasouto. In this way a hermitage was founded, which would eventually be transformed into a monastery; there is documentation of the Bull of Foundation, which was granted by King Alfonso IX.
Centuries later, the inability to maintain the monastery financially meant that it became the property and patronage of the cathedral chapter of Santiago de Compostela, which ceded the usufruct to the Franciscans.
The entry of the friars necessitated a series of architectural modifications, and from 1392 onwards a series of extensions, restorations and reforms began, which lasted until the 15th century. The monastery was so important that in 1520 Emperor Charles I of Spain and V of the Holy Roman Empire retired there to spend Holy Week.
With the confiscation of Mendizábal, the building was seized by the State. After a long lawsuit, it ended up as the property of the Duchess of Medina de las Torres, who offered it back to the Franciscans, who, having found another monastery to live in, decided to decline the offer. Thus, the Duchess of Medina de las Torres restored and adapted it to the aesthetics of a Galician pazo.
The complex that currently constitutes the pazo of San Lorenzo is surrounded by a forest and splendid gardens totally surrounded, in turn, by a wall covering an area of more than 40,000 m².
The church has a Latin cross plan with a single nave with four bays and a short transept, with a quadrangular chancel, as is usual in pre-Romanesque or early Romanesque churches. All these spaces are covered with a barrel vault reinforced with transverse arches, which gives rise to groin vaults between the different sections of transverse arches.
When the monastery was converted into a private residence, various alterations were carried out, such as the construction of the dining room, which was built where the monks' cells should have been. It was covered with a coffered ceiling of Sevillian tiles, and the beams were painted with the family's own heraldic motifs. The dining room is decorated with a pair of tapestries from Flanders, the most interesting of which, depicting the chariot of the Virtues, is located at the back of the room, as well as two coats of arms that have belonged to the owner family over the centuries.