An archaeologist has sparked a Da Vinci Code-style hunt for the Holy Grail after claiming ancient records show it is buried under a 6th century church in Rome.
The cup - said to have been used by Christ at the Last Supper - is the focus of countless legends and has been sought for centuries.
Alfredo Barbagallo, an Italian archaeologist, claims that it is buried in a chapel-like room underneath the Basilica of San Lorenzo Fuori le Mura, one of the seven churches which Christian pilgrims used to visit when they came to Rome.
Mr Barbagallo based his claim on two years spent studying mediaeval iconography inside the basilica and a description of a particular chamber, in a guide to the catacombs written in 1938 by a Capuchin friar named Giuseppe Da Bra.
The friar describes a room of about 20 square metres with a vaulted roof ceiling. "In the corner of a wall-seat there can be seen a terracotta funnel whose lower part opens out over the face of a skeleton," he wrote.
Da Bra then explains that giving liquid refreshment (refrigerium) to the dead was part of ancient funeral rites.
According to Mr Barbagallo, who heads an association called Arte e Mistero [Art and Mystery], this funnel is the Grail.
He also points out to several beautiful mosaics and frescos in the basilica which feature images of the sacred cup.
Mr Barbagallo added that its presence in the church fits the sketchy accounts of its early guardians.
In 258 AD, during a phase of Christian persecution, Pope Sixtus V reportedly entrusted the treasures of the early Church to a deacon called Lawrence, Lorenzo in Italian. This deacon was martyred four days later and since then no one has ever seen the Grail.
Various legends have it that the cup, given the name Holy Grail in the Middle Ages, was taken to different countries - including Britain.
Dan Brown’s work of fiction, The Da Vinci Code, said the cup had been buried at Rossyln Chapel in Scotland, and sparked off a stampede to the isolated location as thousands flocked to see it for themselves.
Mr Barbagallo said he believed it never went anywhere, and stayed with St Lawrence in his tomb.
Emperor Constantine built a shrine on the site of Lawrence’s martyrdom in the 4th Century and the main part of the Basilica of San Lorenzo Fuori le Mura was built in AD580 on the same spot.
The catacombs where Mr Barbagallo believes the cup to buried come under the authority of the Vatican’s Pontifical Commission for Sacred Archaeology.
A spokesman said: "We are aware of the reports and a few weeks ago made an initial investigation of the area with the possibility of opening the catacombs up but as yet no decision has been made."
... I don't think that's what 'refrigerium' was (I thought it was just an annual commemoration-of-the-dead meal ... a carryover from pre-Christian funeral rites), but I'll happily be corrected on that score.