During August and September 2022 a program of repair and rebuild took place to ensure stability of the section of wall immediately to the north of Micklegate Bar. The works involved the rebuilding of part of the parapet wall and two investigative trenches to the exterior rampart and walkway.
It was necessary to partially dismantle the wall face to investigate the cause of the movement and repair it. Facing stones were removed from six courses as well as the coping stones. The stonework was carefully taken down course by course over several days and marked, recording their row number and position within the row. Each stone was inspected by the archaeologist for tool and masons’ marks, but none were identified.
The inner and outer faces of the wall had separated from the wall core, presumably because they had been re-built in the past and not properly tied in to the original core material. The outward movement had caused voids to open up between the core and the facing stone and was the cause of the cracks which had become visible from the outside.
Once the stonework was removed the wall core was consolidated with lime rich mortar and strengthened stainless steel ties. The facing stones were then reinstated in both faces of the wall.
The wall was recorded by photogrammetric survey prior to dismantling.
The works provided further information relating to 19th and early 20th century alterations to the structure and walkway.
The full report can be read here.