Lippitts Hill: Anti-Aircraft Operations Room (Bunker)

This is an Anti-Aircraft Operations Room built around 1951 for the War Office, designed by the Ministry of Works. It was constructed of reinforced concrete with steel blast doors and ventilators.

The building is square in plan and comprises a two-storey, semi-sunken reinforced concrete structure. At its centre is an operations/plotting room, surrounded on both floors by a circulating corridor. Further rooms include control cabins, offices, communications rooms, plant rooms, latrines, and dormitories.

The design was intended to resist the effects of blast, potentially from nuclear or conventional bombs. Consequently, the structure has no windows; the only openings are two entrances, ventilator grilles, a standby generator exhaust, and a ventilation flue protruding from the roof above the plant rooms. The main entrance is centrally located on the north-west elevation, and the second on the south-east elevation, both at ground level. Each entrance is protected by open-sided concrete blast wall porches and features double steel blast doors.

Entering at the upper-floor level (north-west elevation) leads into a reception/security room, connected to a dog-leg circulatory corridor. This corridor provides access to rooms arranged around the central, full-height operations room. While rooms have been adapted for alternative uses over time, their original functions included a tactical radar control room, radio-telephony room, telephone-frame room, and rest rooms. The operations room’s well is accessed from the corridor via doorways, offering views from first-floor viewing galleries supported by plain tubular steel columns. These galleries have anti-reflection Perspex windows, and the blank wall retains a full-width blackboard originally displaying situation tote and map boards.

The upper-floor corridor is accessible externally from the north-west and south-east entrances, and internally from the lower floor via stairways. The lower floor includes a series of rooms arranged around the operations room, likely including latrines, rest rooms, a NAFFI, a room for civil servants, a switchboard, and various offices. Most rooms on both floors retain their original plain wooden doors, timber-framed internal hatches, and a kiosk window in the reception area. Original box ducting for the ventilation system is intact throughout, and the original air conditioning plant and filtration system also appears to be largely intact.