M72 East Cliff Coastal Defence/Chain Home Low Radar Station

Second World War Coastal Defence and Chain Home Low Radar Station M72 at East Cliff on Portland, operational between 1941 and 1942. The station comprises two red brick buildings situated on an exposed limestone cliff with a dramatic drop to the sea.

TRANSMITTER AND RECEIVER BLOCK

A rectangular single-storey building approximately 3 metres high, roughly oriented north-south and located close to the cliff edge. It is constructed of red brick with concrete lintels and a flat concrete roof that extends beyond the external walls, of which fragments of bituminous waterproof membrane remain. Two straight brick piers flank the east and west elevations.

The building has doorways on the east and south elevations with surviving metal frames from former blast doors, though no doors remain. Four window openings pierce the east elevation, one in the north, one in the south, and two in the west; all have had modern mesh inserted and retain internal shutter brackets, though no original blast shutters survive. The window to the east elevation retains its metal window frame. Small regularly-spaced rectangular ventilation openings are located on the north, east and south elevations. Evidence of the transmission of power from the room below to the roof survives in the form of circular holes that would have housed the turning mechanism.

Internally, the building comprises three rooms: two small end rooms flanking a larger central plotting room, linked by doorways with fragments of sliding mechanism remaining. The ceiling is bare concrete. Remains of interior paintwork survive in the plotting room and fragments in the end rooms. No fixtures and fittings remain, but witness marks show where cable ducting and equipment were positioned. A small brick chimney encasing a ceramic pipe, which would have housed the turning mechanism for power transmission to the roof, remains. Metal brackets survive between walls and ceiling in the corner of each room.

STAND-BY POWER-HOUSE

Located approximately 20 metres north-west of the transmitter and receiver block and partially subterranean. It is an irregular T-shaped building constructed of red brick with a reinforced concrete element at the southern end and concrete roof. It stands approximately 3 metres tall with no windows. Small regularly-spaced rectangular ventilation openings are located on the north-east and west elevations.

The southern end features a concrete wraparound porch with three access points and an additional open shelter, possibly a fuel store. Internally, the building comprises one main space with the wrap-around porch to the south providing three open access points.