This name has been given to a vast system of catacombs, near Ponte Fonnaia, dating back to a period between III to V century a.C. It is the only example existing in Umbria of an underground Christian cemetery of vast proportions. The only Christian catacombs in Umbria are hidden among wheat fields and houses, probably built by the Christian community of the vicus, which developed very early (the hagiographic legend of San Brizio indicates the I-II century), and that was certainly very large (more than 300 burials were identified in the catacombs). Since 1948 the name of the catacombs is linked to the memory of San Faustino: in that year his bones were found in the abbey of the same name, not far from this area. The catacombs were partly filled inafter the abandonment of this stretch of the Via Flaminia, and remained unknown until the '600. We know from a letter from the nobleman Giuseppe Mattei from Todi, dated 1691, that the place is named Grotta Traiana and its description is quite suggestive: "you enter into the jaws of a large travertine rock, I you'd rather bend over and take a light with you, because you'll go into the darkness. Inside, after the descent, there are three underground tunnels all carved with a chisel"... The catacomb is not the size of the more well-known Christian catacombs of Rome, but still has an articulated structure, composed of a main ebbing corridor about 25 meters long and 4 meters high. In ancient times it was accessed from a steep staircase carved into the rock, now worn out and hidden beneath the modern iron staircase. Four lateral tunnels of different lengths branch off symmetrically from the central corridor. You may also notice small niches for the burial of children. Many burials are closed by slabs of marble or large tiles of clay and many tombs, called formae, are also dug in the ground. There are numerous graffiti with the symbol of the cross, palm or fish, related to the figure of Christ. Particularly interesting is a bull-shaped sarcophagus that led to the theory of a place dedicated to the cult of Mithras, then adapted to the Christian cemetery. Few archaeological finds: noteworthy the absence of inscriptions, due to the illiteracy of the population of the countryside. A small basilica next to the catacomb oriented to the east, rectangular and with a semicircular apse was discovered in 1997, thanks to the excavation allowed by the Pontifical Commission for Sacred Archaeology, and conducted by the Superintendence for Archaeological Heritage of Umbria. The building is probably connected to the nearby catacombs and occupied by 19 different types of tombs carved into the rock, the one located near the apse of a monumental kind, with arcosolium masonry. The artifacts found, bill gross oil lamps, pottery fragments and coins, are of the same period as those found in the catacombs, proof that the cemetery and the underground basilica above are contemporary. The presence of such a complex demonstrates the early spread of Christian worship in the area of Martana and it also emphasizes the concentration of population in the whole area, albeit of modest social level. The catacomb was obviously forgotten when this stretch of the old street lost its importance, and was gradually buried by the disastrous floods of Naja. Only in 1600 there was news of Trajan cave, named after the local family Traia, or because it was used by Trajan as an underground military passage; later on silence fell again until 1900 when it was mentioned at the Second Congress of the catacombs of Christian Archaeology.