Saint Gatien's Cathedral is a Roman Catholic church located in Indre-et-Loire, France. It is part of the Archdiocese of Tours and is the metropolitan cathedral of the Tours ecclesiastical province. The edifice was built between 1170 and 1547. At the time construction began, the church was located at the south end of the bridge over the Loire, on the road from Paris to the south-west of France. It has been a classified monument historique since 1862.