This door can be found in the north aisle of the cathedral choir. It is constructed from four vertical panels of oak and overall measures 6 ft 5 ins high and 2 ft 9 ins across. It leads to a staircase that was built in the time of Lanfranc (1070s) which led to the former chapel of St Blaise. The wood has been dated by dendrochronology (tree rings analysis) to around 1180 but the metalwork is more problematic. The large 'C' clasps seem to be the work of Lanfranc (1070s) but the horizontal straps, with surface cross-hatching, appear to be the work of 1180s. A plausible scenario is that the door was partially destroyed in the fire of 1074, the 'C' clasps were re-used after the fire, but strengthened with new horizontal straps.
What to see:
the oldest door in the cathedral and one of the oldest in England (Image 1)
detail of the 'C' clasps (Image 2)
detail of the added horizontal straps (Image 3)
Sources: Canterbury Cathedral Chronicle 1980 article by John Fletcher