It's worth going early in the morning when no one else is around (before the tour buses arrive). With no one around, it can be a great experience. There are guards up above and also at the bottom of the main shaft.

The catacombs date from the Roman period and were allegedly discovered accidentally when a donkey fell into one of the underground tunnels.

Deep inside the main shaft there is a series of rooms where the remains of the dead were kept. Now all that can be seen are the rectangular niches. There's a triclinium room, where feasts were held for funerals and on each death anniversary. Most of the walls are bare rock, but there are also some elaborate wall paintings.

The lower parts of the site are flooded and although there are planks to walk on it can get muddy if it has rained recently.

Bring a flashlight and shoes that can get muddy. Cameras are not allowed in order to preserve the wall decorations.