The Catacomb "Ad Decimum" was casually discovered in the beginning of the 20th century. Some peasants were working the soil of the vineyard placed above; the earth fell down under the burden of the plough, and a staircase leading to the old cemetery appeared. The whole district was well known to the archaeologists of the period, being very rich in remains of ancient large Roman villas.
Archaeological discoveries had always been numerous in the environment, and just in that place the presence of a dwelling center could easily hinted at. Such an urban nucleus has been identified by the scholars as the "Community of the Decimenses", i.d. of those who inhabited the tenth (decimum) mile of the Via Latina, just in the meeting point with the Via Valeria (the last one being called today Via della Cavona). As the inscriptions found at that placed witness, the habitants belonged probably to the middle-low class; they were perhaps the same peasants who worked for the neighbouring villas.

The Catacomb is placed now not far from the branching-off of the Via Anagnina; it shows about 1000 tombs dating back to the 2nd/5th century a.C., and it is spread out for about 250 meters. The catacombs proper may be reached, beyond an iron gate, coming down for the 27 steps, in ancient times covered with marble slabs, which are protected now by a recent brick building.
In the inside the galleries were directly digged into a peperine bank and they exhibit two sky-lights, one of which, placed just after the second gallery, is very high; on its side is a deep well: according to the scholars, it could be either a cistern on a water-pipe supplying water to the villas all around.

All of the galleries present a barrel-vault ceiling, that in ancient times was covered with plaster, whose remains are still well visible. Going on farther, one notices that a relief of about one meter exists between the galleries, so that they are called by the scholars "Catacombs with a double adjacent ground".
But the main feature of this cemetery is the presence in it of a great number of epigraphs and graffiti on marble slabs which served to close the niches, containing one or more corpses. Among them, the most outstanding one is the so called "Good shepherd" epigraph; the Latin inscription says: "To the dearest, well-deserving brother Marcianus, Hilarus made in peace"; on one side can be seen a "Good shepherd" placed between two palm trees and on the other a pot whence some twigs shoot off, nourishing two birds with their grains.

Just as every other catacomb, this one too is in rich in fictile tegulae, serving to close the niches; with their seals they help not only to understand the origin, but also the date of both the materials and the burials.

Pictorial remains are very scanty in the catacomb "Ad Decimum", because the old paintings were severely damaged by dampness and time. The sole pictorial surviving scene is the one found on the so called "Traditio legis" arched room: in the center of the bottom wall the nimbused Christ lifts his blessing right hand; with his left hand he delivers a law scroll to saint Peter who, kneeling and with the Cross on his shoulders, receives it with his hands wrapped in the pallium. On the scroll the inscription "DOMINUS LEG(em) DAT" can be seen. On the left side Saint Paul holding the sword is painted between two palm trees, on one of which the phoenix roosts. On the left panel the draped owner of the tomb, "BIATO", is drawn between two saints.

Paola Micocci

The map of the Catacomb