A Lady chapel or lady chapel is a traditional British term for a chapel dedicated to "Our Lady", Mary, mother of Jesus, particularly those inside a cathedral or other large church. The chapels are also known as a Mary chapel or a Marian chapel, and they were traditionally the largest side chapel of a cathedral, placed eastward from the high altar and forming a projection from the main building, as in Winchester Cathedral. Most Roman Catholic and many Anglican cathedrals still have such chapels, while mid-sized churches have smaller side-altars dedicated to the Virgin.

Rochester Cathedral, formally the Cathedral Church of Christ and the Blessed Virgin Mary, is in Rochester, Kent, England. The cathedral is the mother church of the Anglican Diocese of Rochester and seat (cathedra) of the Bishop of Rochester, the second oldest bishopric in England after that of the Archbishop of Canterbury. The cathedral, built in the Norman style is a Grade I listed building.