St John's Chapel, London

It is overseen by the Canon of the nearby castle Church of St Peter ad Vincula, who is the chaplain of the Tower.

Constructed from Caen stone imported from France, St John's has a tunnel-vaulted nave with groin-vaulted aisles and an east apse, above and around which curve the gallery.

[citation needed] Thick, round piers support unmoulded arches, notable for their simplicity, with simple carvings of scallop and leaf designs providing the only ornament.

The programme of decoration was expanded by King Henry III, under whose orders three stained glass windows were installed in 1240.

[2] During the Peasants' Revolt of 1381, a mob gained access to the tower and found Archbishop of Canterbury and Chancellor of England, Simon Sudbury, at mass in the chapel.