San Pietro, Tuscania, Romanesque church building in Tuscania, Italy

San Pietro is a Romanesque church on the hill of the same name outside Tuscania. Its facade has a central section with a large rose window framed by the symbols of the Evangelists, a blind loggia of ten columns, and a main portal with three recessed orders and a mosaic lunette. The interior has three naves separated by low stone walls with seats, a raised presbytery with an 11th-century ciborium inscribed 1093, and a crypt with Gothic tracery.

The date of San Pietro is debated: Pietro Toesca argued for an 8th-century origin under the Comacine masters, while more recent studies place the building in the 11th century; an inscription on the ciborium reads 1093. Between the late 12th and early 13th century the two bays were rebuilt and the present facade erected. The church was Tuscania's cathedral until 1573, and the 1971 Viterbo earthquake destroyed its rose window.

The Cosmatesque floor of the central nave marks out the footprint of the earlier building, and the raised presbytery holds an 11th-century ciborium inscribed with the date 1093. The left nave keeps several Etruscan sarcophagi, and the main portal was carved by a Roman marble worker of the Cosmati school, with zodiac signs and seasonal labours on its jambs.

The church stands on the San Pietro hill above Tuscania, reached on foot from the town; the facade opens onto a grassy clearing between the canons' palace and three surviving defence towers. The tall apse faces the built-up centre. Since December 2014 the site has been run by the Italian culture ministry through the Lazio museum network, so check opening arrangements before setting out.

The crypt has Gothic tracery, and one stretch of it is older than the rest of the building, with capitals and marble fragments suggesting an earlier church on the site. The 1093 date carved on the ciborium is read by some scholars as the year the whole basilica was rebuilt.