St. Mary in Castro, Dover

Saint Mary in Castro, also known as Saint Mary sub-Castro ("Saint Mary in the Castle"), is a historic church situated within the grounds of Dover Castle in Kent, southeastern England. This heavily restored Anglo-Saxon structure is adjacent to a Roman lighthouse (pharos) that was repurposed as the church bell tower, creating a unique blend of Roman and medieval architecture. As the garrison church for Dover Castle, it continues to serve both the local community and military personnel.

Dover, a strategic southeast England port near the White Cliffs, boasts a rich Roman heritage, including two lighthouses from around AD 130. The Eastern pharos, now adjoining Saint Mary in Castro, originally had eight stages, four of which remain. A later addition transformed it into a bell tower, linked to the church by a passage.

Saint Mary in Castro's architecture blends Anglo-Saxon origins with medieval additions. Notable Anglo-Saxon features include the 28-foot-high arches with tile stripwork, double-splayed round-headed windows, and the south doorway with alternating slabs. Medieval enhancements include a vaulted altar recess in the nave's southeast corner and, during Henry III's reign, the addition of three altars dedicated to Saints Edmund, Adrian, and Edward.

Saint Mary in Castro, a Grade I listed building, continues to serve as a place of worship for the Dover garrison and local community. Its churchyard once served as a burial ground for garrison soldiers. Unique features include the pharos-turned-bell tower, a rare Roman structure adapted for Christian use, evidence of a west gallery in the nave, and Victorian-era enhancements such as mosaic work and a vestry.