the W tower is C14.
By the mid C14 there was also a S aisle and porch, later demolished.
The C14 W window is of two trefoiled ogee lights with a quatrefoil in the head and a hood mould.
There are single light windows in the bell stage, and two gargoyles below the parapet on the W. The unified nave and chancel were rebuilt on a very small scale in 1781, reusing older materials including a late C11 or very early C12 N door with chamfered imposts, now blocked, and a late C12 or early C13 S door with roll moulded orders on detached shafts (one replaced in wood) with stiff leaf capitals.
The gargoyle above the W window is probably late C18 or early C19.
The tall C14 tower arch has two chamfered orders, the outer continuous, the inner on polygonal shafts with moulded capitals and bases.
The bell frame is late medieval.
E window has late C19 glass by F R Leach with yellow floral and geometric quarries.
A church was built here shortly after the Conquest in 1066, and the N door probably dates to the late C11.
Always a small, poor church, by the mid C14, St Peter's had a nave, chancel, S aisle
porch and a W tower, and there was a guild in the church in the C15.
In 1503 money was left for three windows on the N side.
From the mid C17, the parish was religiously linked with that of St Giles, although it remained administratively separate.
The church had new furnishings in the late C17 and early C18, and although in an acceptable state in 1743, was ruined by 1772.
SOURCES RCHME City of Cambridge II , 287-88 Pevsner, N., Buildings of England: Cambridgeshire Butler, L, Church of St Peter REASONS FOR DESIGNATION The Church of St Peter, Cambridge, is designated at Grade II* for the following principal reasons: * Medieval parish church with late C11 origins