History of the Rome Catacombs

Nineteen centuries in eight movements: why the dead left the city, who cut the galleries, why they filled with pilgrims, and how they were lost for eight hundred years.

Why the dead left the city, from 450 BC

Roman law forbade burial inside the walls. The prohibition goes back to the Twelve Tables in the middle of the fifth century BC and it applied to everyone — pagan, Jewish and later Christian alike. The consequence is visible on any map: every cemetery in Rome lines a consular road heading out of town, and the Appian Way carries more of them than any other.

That single rule is why a visit to the catacombs is a trip rather than a stroll, and why the tours that include a transfer are buying you the thing that is actually difficult.

The first galleries, late 2nd century

Christian burial underground begins in the second half of the second century. The earliest areas at Priscilla and Domitilla start as private hypogea on family estates, then grow outward as communities took them over. The choice was practical rather than symbolic: land above ground cost money, and the rock below it did not.

The fossores and the century of expansion

The diggers were the fossores, a recognised trade who cut the galleries by hand and sold the plots. They appear on tomb slabs with their picks and lamps, and their work turned scattered chambers into a system. Through the third century the galleries multiplied, level beneath level, until San Callisto alone ran for kilometres.

How they did it without the roof coming down is a story about the rock, and it is told on how the catacombs were dug.

Damasus, 366 to 384 — a cemetery becomes a pilgrimage

Pope Damasus I did more than anyone to make the catacombs a destination. He sought out the tombs of the martyrs, cleared and enlarged the approaches to them, and had verse inscriptions cut by the calligrapher Furius Dionysius Filocalus in a lettering so distinctive that fragments are still identified by it today. Stairs were widened and light shafts opened so crowds could reach the shrines.

This is the moment the catacombs stop being a cemetery and start being a route. It is also why the sections open to visitors today are the ones Damasus made accessible seventeen centuries ago.

Burial stops, the relics leave, 5th to 9th centuries

Burial underground ends in the early fifth century, as Christians returned to open-air cemeteries and to churches. The galleries stayed places of pilgrimage for another three hundred years. Then, as the city shrank and raids on the unwalled suburbs grew, the popes moved the bones inside: through the eighth and ninth centuries relic after relic was carried into the churches of Rome.

That is the answer to the question almost every visitor asks underground. The niches are empty because the remains were deliberately removed, not because anything was looted. Once the relics had gone the sites lost their purpose, the entrances silted up, and eight hundred years of forgetting began.

Bosio's lamp, 1593 to 1632

On 31 May 1578 workers digging for pozzolana on Via Salaria broke into a painted gallery, and Rome discovered it had a second city underneath. The man who made something of it was Antonio Bosio, a Maltese lawyer who from 1593 spent nearly forty years crawling through the galleries with a lamp and a notebook, mapping some thirty catacombs.

His Roma Sotterranea appeared in 1632, three years after his death, and earned him the name Columbus of the catacombs. The century that followed was less careful: relics were removed by the cartload and paintings were damaged by the visitors coming to see them.

De Rossi and the science, 1852 to 1894

Giovanni Battista de Rossi turned catacomb exploration into archaeology. He read the inscriptions against the written sources, worked out where the sites should be before digging for them, and in 1854 identified the Crypt of the Popes at San Callisto from a fragment of a Damasan inscription. His three-volume Roma Sotterranea Cristiana set the method the discipline still uses.

The Pontifical Commission for Sacred Archaeology was founded in 1852 to protect the sites, and it still runs them. That is why San Callisto, Domitilla and Priscilla share one €10 tariff and one guided-visit rule — the practical detail is on visiting the Rome Catacombs.

A chronology you can carry

The best way to stand in the middle of that chronology is to go down into it. Rome Catacombs Tours lists the guided departures that reach the Crypt of the Popes and the underground basilica, and the catacombs one by one says which survives where.