Monument record LCS 002 - World War II pillbox within a medieval Abbey chapel

Scheduled 2nd World War Pill Box (within area of Med Abbey)(S1).
A square pillbox, c 4.5m across, is visible as a structure within the walls of the medieval Leiston Chapel at TM47326598 on aerial photographs from 1941 (S2), 1943 (S3) & 1945 (S4). Aerial photographs from 1940 (S5) show that at this date, the pillbox had not been constructed. The pillbox would have been a component of the extensive World War II defences in this area, and would have been situated at the east end of the chapel to take advantage of the camouflage offered by the medieval ruins. The pillbox can still be clearly seen on aerial photographs from 2000 (S6).
Plan, photos and description in (S7).

2008: As part of a grant aided programme of consolidation works to the building known as Minsmere Chapel, English Heritage required archaeological recording and interpretation to be undertaken. The third phase involved the insertion of a World War II pillbox into the eastern end of the structure and utilised the existing architectural openings

At Minsmere Chapel, Old Leiston Abbey. N of Sizewell Power Station - on road between Dunwich and Sizewell. Pillbox, scheduled with the abbey ruins into which it is built (S9).

An English Heritage grant was obtained by the R.S.P.B. to cover the consolidation of the ruined chapel in their Minsmere Reserve. This is the last remaining structure on the first site of Leiston Abbey, founded in 1182. The specified work included minor excavation, photographic recording and an architectural analysis of the chapel.
The building stands on shallow prominence in a pasture. Aerial photographs and a geophysics plot indicate that it is a secondary structure constructed within the footprint of the much larger original abbey church. The building clearly revealed three major structural phases as follows:
Phase I: The lowermost 2.5m of the standing building. Comprising well-coursed round beach cobbles and common flat pieces of ferruginous sandstone. Architectural features associated with this included diagonal buttresses at all four corners, a large east window, a low doorway towards the eastern end of the south side with an internal niche at ground level immediately to the east two windows, one on the south side (later blocked) and one to the north. The obvious truncation of these window openings suggests that the Phase I building had originally been higher, but was subsequently partially dismantled down to a flat consistent level around the whole structure from which Phase II was built.
Phase II: Comprising all of the wall fabric above Phase I to a maximum surviving height of c.5m. The fabric was coursed, again including beach cobbles. However. the ferruginous sandstone was absent, and there was a significant use of red frogless bricks (9 x 2 ¼ x 4 ¼ in) sometimes in discrete courses with some large exotic stone pieces and re-used limestone masonry, particularly on the north side. Some courses exhibited herringbone pattern. Architectural features associated with this phase included two windows, one on each of the north and south sides and a series of putlock holes immediately above the junction with the Phase I fabric.
Phase III: During World War II the structure was refurbished to hold a disguised pillbox built into its eastern end, facing the sea.
The dating of the Phase I and Phase II fabrics relies largely on the background historical data. The Phase I fabric was not inconsistent with a medieval date, but must post-date the translocation of the Abbey in 1363 to its new location. The Phase I building may have been constructed with salvaged materials from the dismantled first abbey, possibly in the later 14th century. The Phase II structure is clearly later in date, but had almost certainly gone out of use by the beginning of the 19th century when probably contemporary drawings show it as a shell without a roof. One possibility is that Phase II represents the refurbishment of the Phase I building to house John Green who, on his resignation as abbot in 1531, became an anchorite in the chapel of St Mary on the old abbey site. A combination of drawings, engravings and photographs then suggest that the structure suffered a gradual, but continual decline until, during the 2nd World War, the Phase III pillbox structure was incorporated into its eastern end, possibly not without some damage to the structure.Included in the Proceedings of the Suffolk Institute of Archaeology and History annual round up of I ndividual finds and discoveries for 2007 (S9).