The complex of Santa Maria in Gradi has been for several centuries a Dominican convent. Built in 1244 at the behest of viterbese Raniero Capocci, papal notary, it was recovered after important restoration work conducted by the University of Tuscia since 1996. The complex is still impressive and rich in historical and artistic testimonies.
Among these, particular importance is represented by a cloister dating from the mid thirteenth century, where it is still readable in its totality the original decorations: Five pentafore to acute arches on each side, who insist on marble twin columns, 160 in all . Each pillar has a beautiful gargoyles in leonine head, even lacking today, the original discharge function of rainwater, is a decorative element of relief. At the center insists a well of 1557 (the date is engraved on the entablature) resting on a base constituted by recovery tombstones from the ancient church of Santa Maria in Gradi.