It is a heavily restored Anglo-Saxon structure, built next to a Roman lighthouse which became the church bell-tower.

St Mary serves the local population and the army and is the church of the Dover Garrison.

Its proximity to mainland Europe has made it a key military, maritime and trade location for millennia.

The Romans also built two pharoses, possibly c. AD130,[3] on the Eastern and Western Heights above the gap in the cliffs.

However, it is unclear whether this means within the Saxon burgh (usually dated to later than 630) on the Eastern Heights, or within the ruins of old Roman fortifications in the valley.

[dubious – discuss] The Early English vault and the altar recess in the southeast corner of the nave were probably both added to the existing church at the end of the twelfth century.

[6] From 1555 to 1557 the church was walled up as it was felt unsafe due to lack of repairs, though nineteen years later recommendations were made to repair the chancel in stone, glaze (or reglaze) the windows and provide seats for men to hear divine service.

Butterfield's restoration completed the tower and added mosaic work in the nave and a vestry, but was generally held to be less sympathetic than the first by Scott.

A tall round-headed, stone-faced doorway (now blocked and with not much left of its original stripwork outline, but with its typically Anglo-Saxon alternating horizontal and vertical slabs) gave access to the nave from the south.