The Roman Town
Within the town, very little of the rectangular street system has survived, although a great deal of information has been revealed by excavation. The focal point of the street system and nucleus of the town's life was the Forum, a large open market place surrounded by colonnaded shops. The area is roughly indicated by the line of the modern streets of Lewis Lane, Tower Street and The Avenue. (It measured 108 x 68 metres.)
On its south side stood a huge public building, the Basilica. This building was 102 metres long and 29 metres wide and served as the town hall and the courts of justice. Nothing survives above ground although the apsidal western end of the Basilica, where the seat of judgment was placed, is marked out in the roadway at the junction of The Avenue and Tower Street and a plaque is mounted nearby.
Corinium must also have contained many shrines dedicated to Roman and native deities. These together with the public baths, mansion inn and theatre, all essential elements of a large Roman town, have yet to been found. (During the construction of Ashcroft Road, a representation of the three Celtic Mother Goddesses, the Deae Matres, was uncovered and this and other fine religious sculptures can be seen in the museum.)
The most important cult, however, seems to have been that of Jupiter, but in a native form in which a column was set up crowned by a group of statuary. The fine capital of such a sacred column was found in 1838.
It was in the 4th century that Corinium seems to have been the centre of the general wealth of the Cotswolds and on the evidence available was probably the capital of the Province of Britannia Prima. At the peak of its prosperity it must indeed have been a splendid city and excavation has shown the presence of wide colonnaded streets, imposing public buildings including the second largest Amphitheatre in the country and richly furnished private houses, many decorated with fine mosaics (over 80 mosaic pavements have been discovered so far) and painted wall plaster - the typical trappings in fact of Roman urban civilisation to be found in one of the largest and most important towns of the Empire. (Modern excavations continue to reveal buried secrets; there are many examples in the Corinium Museum. The site of the Amphitheatre, to the west of the town, can still be visited, but is little more than a series of imposing earthworks.)
When in the 5th century (AD 415) Roman rule officially came to an end, urban life probably lingered on inside the wall but was eventually largely abandoned. Some Saxons came to settle in nearby Fairford in the upper Thames valley, but not until Cuthwin and Ceawlin took the offensive in AD 577 and defeated three British kings at the Battle of Dyrham did Cirencester fall into Saxon hands.