In September 1991 The Canterbury Archaeological Trust excavated a trench against the city wall at 89b Broad Street. The work was undertaken in advance of redevlopment for the King's School, who funded the work. The sitecode was 89BS91.
The trench ran east from the base of the wall to the street frontage, leaving a gap for access. Excavation ceased at the level of the water table at c. 5.95m OD. The shallow foundations of the Roman city wall were revealed consisting of flints and morar upon which were four courses of water rounded flits. Remnants of a Roman berm, 4.83m wide, was found extending forward of the wall face. Beyond the wall was a substantial ditch which was not excavated though it was thought to be the Roman ditch.
A second ditch cut the first, this had a flat base and was possibly revetted with timber on its western side. A small channel ran along the base of the eastern face. The function of the ditch was defensive, with a secondary use as a sewer for Christ Church Priory, and it had probably been cut in the early Medieval period. A third ditch, also flat bottomed, had been cut, using the base of the second. The ditch seems to have been c. 20m wide and became gradually infilled after having been initially cut in the 14th century. During this time there was a major refortification of the defenses and it is likely the wall was renovated as well.

In May and June 1993 The Canterbury Archaeological Trust excavated within the former gymnasium of the King's School prior to the insertion of foundations, services and flooring for a new theatre. The work was funded by the King's School and the sitecode was SMN93.
The earliest features exposed were of Roman date and included a length of the town wall constructed c. 270-90 AD. It was made of flints bonded in mortar and stood to a height of 1m extending parallel to and below the north wall of the gynasium. The remains of the earthern rampart were also seen to the rear of the wall. Capping the rampart was a 0.7m thick deposit of loam thought to have developed when the rampart was reduced/removed, possibly at an early date, prior to the 12th century and during a period of abandonment.

In 1995 The Canterbury Archaeological Trust took 4x5 rectified photographs of the City Wall at 92b Broad Street before repairs were undertaken.

Pratt, S., 1992, 89b Broad Street (Article in serial). SKE30769.

Ward, A. & Bennett, P., 1995, St Mary Northgate (Article in serial). SKE30262.

Rupert Austin, 2001, Personal Comment Rupert Austin, Inventory List (Unpublished document). SKE28531.