It is estimated that there are more than 1000 km of catacombs running beneath the ground of Rome, and, since they are constantly discovering new ones, we can be certain that there are many more we don’t know about yet. A small Catacomb as it is St. Agnes alone is approximately 600m long, and includes around 5763 graves. The catacombs are located along the roads outside the ancient city of Rome, most between the first and third mile.
Their extension is limited by deposits of volcanic tuff and areas of swampy ground. As demonstrated recently by excavations under St. Peter’s Basilica in Rome and the Hypogeum of Via Latina, pagan and Christian tombs were often located near each other. Pagan burials continued taking place in the area until the fourth century, as demonstrated by pieces of sarcophagi falling into the galleries below. Finally a pagan cemetery would gradually turn into a Christian catacomb.
The Catacombs of Rome are presented as an underground network of corridors of varying width and irregular layout, arranged on one or more floors; some have up to five floors. Along these corridors are niches, or rectangular holes, enclosed by a stone slab. A deceased person was laid to rest in each of these niches. Sometimes the bodies were placed under an arcosolium, a kind of arc carved in the ceiling, which serves to define and enclose the tomb placed under it.
The available space is maximized, as the graves are very close together. In very rare cases, the arrangement of corridors and tombs were lavishly decorated, as in “New Hypogeum” discovered in 1956 at the Via Latina, with its unusual paintings of Pagan and Christian themes. In other cases, ancient stone quarries or natural caves were used as catacombs. Generally, however, it seems that most of the underground tunnels are due to the work of Christians.
ROME - THE CATACOMBS (Rome, Italy) 41° 86' 08.285" N - 12° 50' 65.618" E