A complex of monumental buildings has been located outside the Roman fortress at Caerleon in South Wales

Archaeologists from the University have made a major new discovery that will change the way we think about how Britain was conquered and occupied by the Roman army almost 2,000 years ago.

A complex of monumental buildings has been located outside the Roman fortress at Caerleon in South Wales, which is likely to lead to a complete rethink of one of the country’s most important Roman sites.

The discovery was fortuitous - students from the School of History, Archaeology and Religion were learning how to use geophysical equipment in fields outside the fortress that were not thought to have been extensively occupied in the Roman period. 10 days later, the students and their tutors had revealed the outlines of a series of huge buildings squeezed into the ground between the amphitheatre and the River Usk.

Dr Peter Guest, Senior Lecturer in Roman Archaeology at the School said: “Caerleon is one of the best-known Roman sites in Britain, so it was a great surprise to realise that we had found something completely new and totally unexpected. We’ve discovered the remains of several very large buildings shown remarkably clearly on the geophysical surveys completed by our students.

“It is difficult to be certain about what we have been found because nothing like this has been discovered in Roman Britain before.  The buildings’ ground plans suggest that they were of some importance. We think that they could have included markets, administrative buildings like town halls, bath-houses, store buildings, or even possibly temples. The biggest is enormous and must be one of the largest buildings known from Roman Britain. We can only guess what it was for, but at the moment we’re working on the idea that it had something to do with a harbour on the river, although it does look uncannily like a residential villa building - if that’s the case it was built on a palatial scale.

“The layout and scale of the buildings look like they should be at the centre of a town or city,” continued Dr Guest, “but here at Caerleon we seem to have the central public spaces without the surrounding city - where are the people who would have used these buildings? Perhaps they were intended for the legionaries of the Second Augustan, but it is also possible that this is the first evidence for Roman plans to develop the fortress at Caerleon into a major settlement in western Britain - plans that for some reason never came to fruition. That’s the great thing about an archaeological discovery like this - lots of new questions that we just don’t have definite answers to at the moment.”

Caerleon is one of only three permanent legionary fortresses in Britain. The other fortresses at Chester and York are much more difficult to excavate because their remains are mostly buried under cities. Caerleon provides the only opportunity to study the Roman legions in Britain.

The new discovery was made as part of the School’s ongoing excavations at the site. Over the last four years, staff and students have uncovered eight previously unknown barrack blocks, three large granaries, a monumental metal workshop and a very large store building. On occasions, members of the public have also helped with the excavations.

Between 9 August and 17 September 2010, the team of archaeologists, along with staff and students from University College London (UCL) will be at Caerleon for their final season of excavation. Taking place near the site of the new discovery, the team hope to uncover yet more information about the fortress and its inhabitants.

“We will be spending six weeks in Caerleon this summer, excavating within the fortress walls with colleagues from UCL. We hope to reveal yet more information about the fortress and its legion and I am sure that our work will produce some really exciting results,” said Dr Guest. “The dig is open to the public and we’d be delighted to see people coming along with family and friends to find out more about the work we are doing.”