Tarrasa, the ancient Egara, was episcopal see in the Visigothic period, between 450 and 711. This ensemble of three churches, the cathedral dedicated to Virgin Mary, the baptistry to St. Michael and the parrish church to St. Peter, was traditional with the bishoprics of that period so, although they have been built upon rests of previous constructions and partly rebuilt in the Romanesque period, they are considered to belong to the period when it was a bishopric.

Among the episcopal ensemble of three churches in Tarrasa, this one would have been the cathedral dedicated to the Virgin Mary. Built in the 7th century upon a previous church, it was a three nave basilic with an apse. Only the apse, the central nave and the first stretch of the lateral walls have been preserved and they now form a sort of crossing.

Among the episcopal ensemble of three churches in Tarrasa, this one is located more to the north and it originally had a basilical shape with three naves, that later disappeared starting on the second stretch, although in the restoration in the Romanesque period only the central one was re built, forming like the first stretch of the lateral ones, as in St. Mary, something similar to a crossing

This is the third building of the episcopal ensemble in Tarrasa, located between St. Mary and St. Peter. Very well preserved, its plan has the shape of a Greek cross in a square, from which protrudes from the eastern side, an apse with a poligonal shape outside and horse shoe shaped inside. It is considered as the baptistry of the ensemble; a baptismal font was added to in the restoration.

Small hermitage that consists of a nave and an apse, both covered with barrel vault and separated by a horseshoe arch of clear Mozrabic ascription. When the nave’s vault was being built, it was initially covered in wood, the lateral walls were reinforced with attached rounds of arches, also horseshoe shaped, that recall those of St. Miguel de Cuxá; also the door on the southern side was blocked and replaced by another one on the centre of the western side.

A partir de una primera construcción, posiblemente visigoda, formada por una única nave y un ábside trapezoidal, en el siglo X se amplió a una estructura de tres naves y otra transversal a modo de crucero, cubiertas con bóvedas de piedra, añadiendo al ábside inicial otros dos laterales semicirculares. Los distintos espacios están comunicados entre sí mediante arcos de herradura. En su interior existe un interesante conjunto de pinturas mozárabes y románicas.