This collegiate church, was built in the late 13th century on the site of an earlier monastery. It was served by a "college" - clerics who lived in a community but who did not submit to the rule of a monastery. They lived in a house, now destroyed, beside the church. The church was a large and elaborate structure, with an aisled nave (the main part of the church where the congregation sat) and a long chancel (the section of the church where the altar was placed) and has high quality architectural sculpture used throughout. In the late middle ages a massive tower was inserted between the nave and chancel, and in the 19th century this tower was incorporated into the parish church which was built in place of the chancel and which now takes up about half of the building. There were also several other changes made to the church at various periods.