Archaeologists have discovered that what had been thought to be a relatively small, down-market amphitheatre in Britain was in fact a top-of-the-range, though admittedly more intimate, version of Rome's famous gladiatorial arena.

Indeed, this British Colosseum - in Chester - may well have been built as a replica of the one in Rome, possibly on the orders of the Roman Emperor Septimius Severus, who was in Britain at the time.

Although it was much smaller than the Colosseum, its outer wall appears to have had a blind arcade of 80 arches, giving it a superficially similar appearance to the one in Rome. If the archaeologists' calculations are correct, Rome and Chester were the only places in the Roman world to have amphitheatres with that number of arches.

Chester's inhabitants appear to have been enthusiastic supporters of their Colosseum. Evidence suggests that the audience gorged on salmon, oysters, hazelnuts, venison, lamb, pork, beef and chicken. The "entertainers" did not have such a good time. The archaeologists - led by Dr Tony Wilmott of English Heritage and Dan Garner of Chester Archaeology - have not only found broken daggers and bits of shattered armour, but also fragments of body parts.

In all, the archaeologists found 10 pieces of human bone - a bit of jaw, a top vertebra, part of a leg and several fragments of skull (two of which show signs of fracture). In the centre of the arena, a large stone block was found with the remains of an iron tethering ring set in it. It is likely that victims were tied to it while trying to protect themselves against wild animals.

The gladiatorial contests must have been important for the local economy. Outside the building, traders built ovens to meet the demand for roast meat, and stalls almost certainly sold gladiator-related souvenirs.

The amphitheatre, built about AD100, was completely rebuilt about 100 years later to resemble a scaled-down version of Rome's Colosseum.