Riserva Naturale Regionale Monte Genzana Alto Gizio

A church dedicated to St Dionysius is already mentioned in documents by Lucius III in 1183 and Clement III in 1188. It is also mentioned in documents from the 14th to the 16th century.
Until 1589, the church in honour of St Dionysius was called the mother church, but from 1594 the title passed to an unidentified S. Maria della Porta. The name "della Porta (of the Gate)" suggests its proximity to one of the city entrances and is sometimes also attributed to St Dionysius.