The Church of Santa Maria de Arce stands next to the Theodoli Castle, at the highest point of the historic centre: its name “de Arce” comes from the Latin “arx”, meaning rock or citadel, recalling its position. The first construction phase dates back to the 15th century, as confirmed by an inscription from 1489 on a bell, when the church served almost exclusively the soldiers garrisoned near the Rocca.
In the 17th century, when San Vito passed under the rule of the Theodoli family, the new lords of the fief showed their generosity towards the church near their castle by donating a large altarpiece depicting the Assumption, attributed to Carlo Maratta or his school. From the second half of the 19th century onward, successive parish priests transformed its appearance: the two side aisles were built and the vault was demolished and rebuilt, opening six lateral windows. In the early 20th century, Don Guarino Nini commissioned the architect Andrea Busiri-Vici to give the church a new layout, which included moving the bell tower from beside the apse to near the façade, building a new sacristy and creating the Chapel of the Crucifix.
The façade, marked by a single giant order with angular pilasters, ends in a curvilinear pediment topped by a wrought-iron cross; the portal has a simple travertine frame crowned by a mixed-style pediment bearing the marble Theodoli coat of arms. The three-nave interior culminates in an apsidal chapel, with the central nave marked by a rigorous geometric order of pilasters on the load-bearing walls.