During World War II Darwin became a naval base. It suffered its first air attack on 19 February 1942, and within a month of the first air raid Darwin became the heart of the operational base. The Northern Territory contained the largest operational base in the South West Pacific. Adelaide River and Alice Springs were the headquarters of large base establishments and the main north south road from Darwin to the railhead at Alice Springs was built during the war. Nos. 107 and 129 Australian General Hospitals were based at Darwin; Nos. 101 and 121 at Katherine; No. 119 at Adelaide River and No. 65 Camp Hospital at Pine Creek.