The church of St Silvestro is in the centre of Falacrinae, a small Roman settlement near the river in a village of Cittareale. The church is rather small in size and consists of a main building and a sacristy with a crypt. From this crypt, partially enclosed by a wall, it can be deduced that the underlying medieval church dates from between the fifth and tenth century AD. Svetonio speaks of Falacrina as a place of origin of the three Flavian emperors (Vespasian, Titus and Domitian). The name Falacrina comes from Falacro, a Sabine ancient deity. A plaque fixed on 5 December 924 records the date of reconstruction and rededication to St. Sylvestro. It seems clear, then, how difficult it is to determine precisely the genesis of the church that is still surrounded by many mysteries.