The masonary walls of the medieval Guildhall were excavated during an evaluation in 1992. Many of the medieval walls overlay layers and features associated with the Roman Forum (TR 15 NW 2177).

One of the features cutting the Roman layers at the site was an E-W aligned feature which extended beyond the limits of the excavation. The feature had a U-shaped cut and measured 1.1m in width and 1.4m in depth. The context of this feature and its well-compacted loamy fills has led to the interpretation of this feature as a possible laminated foundation to a structure which faced onto the High Street.

Walls predating to the medieval cellar were identified through the excavation, alongside levelling deposits, walls, and floors associated with the medieval cellar. Later robber trenches related to the demolition of the medieval cellar were identified cutting the earlier layers.

Another feature predating the cellar was a rectangular rubbish pit over 0.6m in depth and containing Roman brick and tile, opus signinum, oyster shell, bone fragments, sherds of pottery, and carbon flecks.

One of the cellar walls of the Guildhall is described as follows "the wall's alignment ran parallel to the east side of trench 1 for 0.9m from the north edge before turning to run west under the High Street frontage (not exposed). Three phases of wall construction were visible. The earliest phase was constructed chalk fragments of varying size and lesser quantities of flint and peg tile. It was bonded by an orange-brown mortar containing a large quantity of flint pebbles. Ten irregular courses were visible in its construction and the exposed east face was uneven indicating that it was trench built. The absence of any facing work indicated that the cellar was entirely subterranean. The use of chalk blocks in the construction suggested that the wall was not earlier than the late 13th century" (from the original report, 1). Other medieval walls at the site appear to have reused Roman material within their construction. A series of mortar and clay floors, alongside an early occupation layer containing Roman brick and tile, animal bone fragments, sherds of pottery, and carbon flecks were associated with the cellar.

A N-S aligned medieval drain formed from peg tiles cut the early medieval foundation. This feature measured 0.4m in width, 0.35m in depth, and was visible for 1.8m in length.
"Mortar floors contemporary with this period were also seen, overlain by a levelling deposit the surface of which had been compacted to form another floor surface. Numerous floor layers were observed above this level, some cut by post-holes of unknown function and suggesting a pattern of heavy domestic use of the cellar, including the lighting of fires" (from the original report, 1). An undated stake-hole was also identified at the site.

Further cut features and walls were present at the site to allow rebuilding to take place, the second phase of which occurred during the mid-15th century. The third phase of construction was evidenced through the foundation of a façade wall measuring 0.6m in width, and surviving to a depth of 0.25m. Included in its construction was a large fragment of stone moulding from a window. This phase of construction is thought to have taken place during the 18th century or later.

The projected line of the medieval walls has been mapped onto the GIS. (1)

<1> Canterbury Archaeological Trust, 1992, Excavations at No. 11 The High Street, Canterbury (Excavation archive). SKE30011.