Before they enter this strange realm, visitors to Europe's largest collection of mummies must pass a grim gateway that seems like a portent hewn in stone.
Giant Moorish figures, which recall the ghost of Aladdin's lamp, scowl down at all who venture into the 500-year-old Porta Nuova on foot.
The spot on Italy's largest island of Sicily is a netherworld on the fringe of Palermo's old quarter and the tourist comfort zone with its familiar array of blinking traffic lights and road signs.
The Capuchins built the Ingresso Catacombe monastery in 1534 on a site which at the time was outside the medieval city. The name stands inscribed above the entrance.
Underneath the words is a warder and on quiet days, when many a visitor finds himself or herself alone, he is the last living person many will see for some time. Down in the catacombs there are only mummified corpses.
The path leads down a flight of steps and around a bend in the passageway before the unnerving array of corpses comes into view. They nestle in wall cavities or hang from hooks on the wall. These dehydrated dead have not been laid lovingly to rest but made to stand like the soldiers of a ghoulish army.
There are said to be almost 2000 deceased in the catacombs. The bodies are still dressed in the finery they were wearing when they died - black suits, ball dresses, gowns or military uniforms.
All of the garments are now moth-eaten and full of holes.
The most disturbing aspect of the display is that the bodies are still in various stages of decomposition. Some are little more than skeletons, topped by a bare skull with blackened eye sockets and a wired-up jaw.
Other dead heads are covered with pieces of tautly-drawn leather-like skin, adorned with a few scattered tufts of black hair. They have worn so well because of the special climatic conditions in the catacombs caused by a permanent draught of fresh air and walls of pumice stone that absorb the damp.
As a result, the cadavers tend to dry out rather than rapidly decompose.
The Capuchins discovered this effect in 1599 and the oldest mummified corpse, that of Silvestro da Gubbio, dates back to that time.
It was around then that the monks began lining up their dead along the walls as a pointed reminder to the living.
Their motto: "You will become what we are and we were once what you are now."
The ghoulish idea caught on among the lay population too and after a while wealthy Palermo folk took to visiting the remains of their relatives long after they had shuffled off this mortal coil.
The attraction became so popular that the Capuchins expanded the premises. They adopted the practice of hanging the corpses in a kind of airing cupboard for between eight and ten months before allocating them a niche in one of the halls.
The corpses were arranged according to social status, with men and women separated.
The cult of the dead was officially abolished in the 19th century but the practice continued even after that.
Today's crowd-puller is the mummified body of the infant Rosalia Lombardo, who died of influenza in 1920.
The father of the two-year-old was beside himself with grief and since he was a man of considerable influence, he commissioned embalmer Alfredo Salafia to ensure the best presentation of his beloved daughter.
In delaying the decomposition of little Rosalia's body, the chemist produced a masterpiece of embalming which is sometimes referred to as the "world's most beautiful mummy".
Indeed the pretty girl with the pink ribbon appears so natural and life-like that onlookers often feel an urge to snatch her from the glass coffin and carry her away from these relentlessly grim surroundings.
Visitors to the crypts on a weekday morning may well find themselves alone among the corpses, with only a occasional noise through a ventilation shaft to hint at the world outside.
Most of the mummies stand with their mouths gaping open since their wired jaws have become loose over the years. It is easy to imagine them screaming - except that down here someone has turned off the sound.