The Chapel takes up the south-east corner of this floor and the floor above, and is particularly interesting due to its early date (circa 1080) and perfect condition. It measures 55 feet 6 ins long by 31 feet wide, and has a nave and aisles of four bays and an apse opening by five arches to an ambulatory.
The principal doorway is in the west bay of the north wall, and a second entrance opens from a wall passage at the south-west. The heavy round columns carry carved capitals, some of which bear a T-shaped figure found only at this early date. The arches are quite plain and above them is a clearstory lighted by a second tier of windows; its gallery is a continuation of the wall passages of the second floor.
There are no old fittings in the Chapel; the glass in the windows was part of Horace Walpole's Collection at Strawberry Hill. The institution of the Order of the Bath was very closely connected with this chapel. It was in this Chapel that Queen Mary was betrothed to Count Egmont, proxy for Philip of Spain, in 1554.
Leaving the Chapel by the north door the visitor enters THE SWORD ROOM.