A conical column of tufa that was found in 1880 on this site bears an Etruscan inscription(ca. 4th century BC): "TINIA TINSCVIL".  It probably formed part of an altar dedicated to Tinia (Zeus, Jove) from a temple on the site.  The inscription, which is now in the Museo Archeologico Nazionale, is discussed in context in the page Early Etruscan Inscriptions.

According to tradition, Pope John X founded the church of San Giovanni here in 916, although the complex was not documented until its restoration in 1003, when it was apparently restored and extended by Pope John XVII.  A community of canons was established here by Bishop Sigifredo (died 1028).

The church must have been restored again early in the 13th century (or perhaps it had been taken over by heretics) since Pope Innocent III consecrated it in 1216.  An associated hospice was documented in 1286. 

In 1498, Pope Alexander VI transferred the complex to a congregation of Lateran Canons based at San Salvatore, Bologna. 

A bequest from Bishop Giorgio della Rovere (died 1505) financed the restoration of the complex.  His cousin, Pope Julius II described the church as “vetusta antiquissima et magni edificii” (a venerable, ancient and magnificent edifice).

An earthquake destroyed the church in 1687 and it was demolished a decade later.  It was rebuilt with the opposite orientation and on an octagonal plan, to a design by Giovanni Battista Arrigoni.  The facade was completed in 1857 and the campanile was built in 1928. 

Site

The complex enjoys a stunning position on the edge of the cliff.

Interior of the Church

The architectural fragments and inscriptions that were found nearby in 1912 are embedded in the wall, on both sides of the entrance.  Some probably belonged to an early church on the site, while others are older.

Madonna della Fonte (14th century)

Art from the Church 

Standing Madonna and Child (ca. 1335)

This large wooden statue, which is badly damaged, is now in the Museo dell' Opera del Duomo.  The baby Jesus holds an orb and raises His right hand in blessing.  The Madonna holds [a broken staff ??]

Monastery and Cloister

The canons' residence is to the right of the church.  The original cellars are now occupied by the Palazzo del Gusto and Enoteca Regionale.  The wellhead in the cloister, which is attributed to Antonio da Sangallo il Giovane, was probably built in or soon after 1532, when the canons of received money from the Commune for a cistern here.

If the door to the complex is open, you can see the cloister (1513), which contains an interesting wellhead (1526).  [Arms of Archdeacon Antonio Alberi ??]