World War II Quarantine Anti Aircraft Site, East Arm Darwin From above with the drone. Being a strategic Allied military base during World War II, Darwin was the target of multiple Japanese air raids, with the first in February 1942. More bombs were dropped on the city in this raid than on Pearl Harbor two months earlier. Savage air raids continued to rain across the Top End during World War II, leading to a repositioning of armed forces in the Darwin region. Adelaide River, 113km south of Darwin, become a huge base for Australian and American headquarters. During the period February 1942 to November 1943, Australia came under attack on nearly 100 occasions by the Japanese! Located just 8.53kms east of Darwin, the East Arm Quarantine Anti-Aircraft Battery Site is the only complete gun-site of its type remaining within the Darwin area. Established in 1941, it was highly significant as it was a design that was discontinued by the Defence Force in the mid 1940s and one which is unique to the Northern Territory. The present structures were built in September 1942 by the Civil Construction Corps and personnel of the 2nd and 14th HAA Batteries. The site was used to defend the South West section of Darwin Harbour and was a backup for the Berrimah Station. Local stone was used in the construction. The entry post was constructed solely of local stone with the remaining structures built of aggregate made from local stone. The original structures consisted of four revetted emplacements, a central instrument bunker, accommodation, administration hut, mess kitchen and rifle range. The site comprised four 3.7" Heavy AA guns, a Bofors gun, a Vickers Predictor Mark IV a Height and Range Finder Mark IV Lewis Machine guns and Radar Equipment. During the Japanese raids on 22 February 1942 the guns maintained fire at the enemy with one heavy bomber being shot down. Today the site consists of the revetted emplacements the central bunker and slabs where the administration mess and kitchen buildings stood. The 3.7" guns were removed on 27 November 1944.