San Vittorino is a Baroque former Roman Catholic church in Cittaducale, province of Rieti, region of Lazio, Italy. Soon after completion in 1613, the church collapsed into a sinkhole, and the roofless ruins remain, with the facade sheltering a mineral-water pool that streams out the former portal. The combination of ruins and nature create an air of mystery; the church was used in some of the scenes of the movie Nostalghia.