Severed legs and heads from 20 people have been recovered underneath a great amphitheatre built to provide entertainment for Romano- British Londoners.
The human remains - along with the remnants of a bull, a bear and several horses - were found in the drains underneath the 105m- long (344ft) elliptical arena, built - probably on the orders of the Emperor Hadrian - under what is now the City of London's administrative headquarters, Guildhall.
The discovery, believed to be the first time that remains of any amphitheatre victims have been found, confirms historical accounts of mayhem and slaughter in the arenas, constructed in every corner of the Roman Empire.
In many amphitheatres, thousands of citizens would gather to watch condemned criminals - stripped naked - being ripped to pieces by wild animals or forced to fight each other to the death.
It is estimated that London's amphitheatre had seating for 7,500 spectators. The human remains found in the arena's drainage system include five skulls, six leg bones and jawbones. A bull's skull may be the detritus from a form of bull-fighting in which the animals were pursued around the arena by horsemen armed with spears. The bear bone is almost certainly evidence of bear-baiting.
The excavation team - led by Nick Bateman, an archaeologist at the Museum of London - has also found large numbers of sheep and cow bones, probably from the food stalls which were set up around the amphitheatre on festival days.
The building was constructed about AD120 - roughly the same time that Hadrian ordered the erection of a fort in London and his great northern frontier wall.
The amphitheatre was located just 20m (66ft) from the south-east corner of the military fort which housed London's 1,000-strong garrison. Excavations over the past 10 months reveal that it was about 105m long and 85m (279ft) wide. It may also have been used for military parades and training, and public meetings. Much of the original timber has been removed by archaeologists. It is one of the few large Roman sites to have yielded large amounts of intact woodwork.
The amphitheatre was probably abandoned about AD370, and the first Guildhall built on the site in medieval times.