Insula III is located towards the centre of the Roman town, immediately to the west of the forum basilica. The Society of Antiquaries' excavations at Silchester (1890-1909) defined 37 insulae (Latin for island) or blocks within the walled town. Previously, modern excavations within the walls have re-examined parts of Insula IV (forum basilica and possible church) and Insula IX (domestic housing) as well as the defences themselves and some of their gates. Outside the walls the amphitheatre has been excavated.
During the excavations in Insula IX (1997-2014), quantities of fine architectural stone and other building materials, including imported and Purbeck Marble, were found re-used as foundations in timber buildings and elsewhere in rubbish deposits dating to the late 1st/early 2nd century AD. The inference of these finds is that there were high status buildings which had been both built and demolished before the turn of the 1st and 2nd century. Building of such quality within any town of Roman Britain dating to the 1st century AD is exceptional. What building(s) had they been taken from? Where might such building(s) be located?
One clue was offered by the Victorian excavation of Insula III in 1891 where the remains of a possible bath house were discovered in its south-east corner. The excavators were not confident of their interpretation and their description of their findings suggested that these and other building remains were found at some depth, so indicating a possible early date for them.
In 2013-14 we re-examined the possible bath house and found the remains were indeed early, dating to the 1st century AD. The foundations did not, however, belong to a bath house, but to a large town house whose footprint, we found, extended beyond the limits of our trench.
These remains were distinct from a later phase of occupation which comprises the very fragmentary remains of masonry-founded buildings fronting on to the two streets, rubbish pits, an enigmatic hypocaust structure, perhaps a corn-drying oven, and associated with a stone-lined drain, and a hearth of reused tile.
The first Roman phase is extremely interesting, not just because of such an early date for a masonry-founded building, but also because it is clear that the building extended both north and west beyond the area we had opened in 2013-14. What we seek to discover this summer and next is how far the remains extend across the insula (block). Was there a comprehensive plan for the initial development of Insula III? Is there any connection with the Nero tiles we have found in the Insula?
We are opening two trenches, first in the north-east corner of the block, then in the north-west corner. Tantalisingly, one of the foundations marked on the Victorian plans in the north-east corner aligns exactly with one to the south. Is the insula occupied by a single building in the mid-to-late 1st century AD? Did the colonnade extend all along the north-south street? Did the colonnade return along the east-west street?