The territory of Vetralla was intensely inhabited by the Etruscans, as shown by the rich archaeological evidences, like the rocky necropolis of Norchia and Grotta Porcina. In Roman times the areahas grown thanks to the Via Cassia (which passed through it): in the site occupied by the Church of Santa Maria in Forcassi stood the ancient Forum Cassii, a mansio indicated on the Tabula Peutingeriana, located along the consular road. Some ruins of the mansio and some well preserved parts of Via Cassia are all that remains of the ancient town. A permanent settlement was formed only in the Dark Ages, when the population moved to Monte Fogliano, a more easily defensible site, where today the modern Vetralla still stands. In 728 AD it becomes part of the State of the Church: in Vetralla Pope Eugene III ordered the Second Crusade (1145 AD). Over time the feud of Vetralla was assigned to several noble families linked to the papacy, like Orsini, Di Vico, Cybo and Farnese. Today the town offers a long promenade that crosses the historic center, which is overlooked by palaces and churches: that of St. Francis (12th c.) preserves the most important cycle of Franciscans frescoes outside Assisi. Ancient columns and materials, probably from Forum Cassii, have been reused to built the church. One of the towers of the ancient city wall is home to the Museum of the City and Territory, where an extensive documentation on wine, rural traditions and handicrafts is preserved.