And more than 60 of these catacombs — intricate labyrinths or tunnels with recesses for burial chambers — were built in Rome from the end of the second to the early fifth century CE.

While most catacombs were the final resting places for Christians, some were built for Jews — notably in the gardens of Rome’s Villa Torlonia, which was built around 200 years ago for the wealthy Torlonia banking family.

While fascist dictator Benito Mussolini took over the site in 1929, the villa and its gardens remained unused for many years after his death in 1945.

Now the site has been restored and is open to the public — except the two ancient Jewish catacombs.

During a private tour, however, I was able to look inside.

Cristiana-Barbara Pazienti, who works for Rome tourism agency Atlazio, and Simona Morretta, a senior archaeologist from Rome’s State Archeological Commission, guided me around the long narrow passageways, which were unearthed in 1918 by workers altering the gardens.

They are surrounded on both sides by multiple levels of niches, or loculi, carved out of the rock, extending from ceiling to floor.

Bodies were placed in these niches which were then sealed with rubble and bricks and then coated over with a layer of lime.

There is also a geniza — a depository where holy documents were deposited.

These catacombs are extensive, extending for more than 13,000 square metres with over 1,000 metres of galleries on the two floors. To access them we had to descend a series of stairs.

The main interest in these catacombs is the plethora of beautiful coloured frescos on the walls and part of the vaulted ceilings.

These represent characteristic iconographic Jewish symbols and many are in an excellent state of preservation.

These include the seven-branched menora, shofar, ark with the law tablets, etrog, lulav, circumcision knife, cruse of oil and matzot.

There are also depictions which may possibly represent the façade of the Temple destroyed in 70 CE by Titus.

Additional frescoes include geometric patterns, grapevines, birds, plants and fish. These are not specific to Jewish catacombs and are also seen in those of Christian origin.

Not unexpectedly, there are no depictions of humans consistent with the Ten Commandments which prohibited displays of graven images. There are also stamped tiles with the name of the ancient Roman workshop.

Interestingly enough, the inscriptions found in these and other Jewish catacombs are in Greek and not Hebrew.

Radiocarbon testing using organic material incorporated during the construction of the catacombs revealed that these catacombs date from about 100 BCE.

According to Professor Leonard Rutgers, who conducted the tests, these specific catacombs came into general use in the first century and predate Christian catacombs by at least 100 years.

This implies that burial of the dead in catacombs may have begun as a Jewish custom and that it was subsequently adopted by the Christians.

However, the question of the precise dating of these catacombs is not definitely resolved.

Other archaeological findings such as oil lamps found in the catacombs of Villa Torlonia date from the end of the second to the early fifth century CE.

The Roman Jewish Diaspora community is the second oldest in the world and dates back to the first century BCE.

Jews would have likely chosen to bury rather than cremate their dead since cremation is prohibited by Jewish law.

Roman jurisdiction forbade burial places in the city itself and in view of the scarcity of land, catacombs were established in the soft volcanic rock outside the city walls.

Today, the extensive gardens of Villa Torlonia form a large municipal park. The villa itself is opulently decorated.

The central feature is the two-story high ballroom and vault, lined with paintings, stuccoes and marbles. On the second floor is Mussolini’s bedroom with the original furniture. The management of the catacombs was originally under the direction of the Pontifical Commission of Sacred Archaeology.

The current custodian is Rome’s State Archeological Commission. Because of dangers of rock falls, noxious gases and the issue of preservation of the frescoes, these catacombs are closed to the general public. But discussions are under way with archaeologists and the Jewish authorities in Rome with a view of eventually opening this fascinating place to tourists.

And it is anticipated that the restoration of the catacombs in Villa Torlonia will begin at the end of the year.