(Collecta: S. Quiricus)
(Image source)
From the Churches of Rome wiki:
San Martino ai Monti is an ancient church dedicated to St Martin of Tours, the 4th century Bishop of Tours.
The church was probably one of the tituli, the first parish churches of Rome, known as Titulus Equitii. It was founded in the 3rd century, or possibly in the 4th century by Pope St Sylvester, as a 'house-church' in a private home [1]. A local synod was held here in 324 to prepare for the Council of Nicaea.
It was rebuilt in the 6th century by Pope Symmachus (498-514), and dedicated to Pope St Sylvester and St Martin of Tours. It is therefore also known as Santi Silvestro e Martino ai Monti.
The present church was built by Pope Sergius II (844-847). The basilical plan was preserved, and columns from the first church were reused. Many relics of early martyrs were brought here from the suburban cemeteries, which were threatened by raiders. Among those were the relicts of St Sophia of Rome. The most important are the relics of Sts Artemius, Paulina and Sisinnius, which were translated from the Catacomb of Priscilla and now lie under the high altar.
In the 8th century the relics of St Soteris were brought here from a church on Via Appia before that church was destroyed.
It has been restored several times since. In 1570, St Charles Borromeus has some alterations made. The last major work was done in 1650 by Filippo Gagliardi.
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Excavations have revealed Roman houses below the church, and one of them is thought to have been used for Christian worship before tolerance was granted by the emperor. It is however possible that they were adapted for Christian worship at a later time...
