The Allies continued to develop the base area at Milne Bay in support of the counter-offensive along the northern coast of Papua and New Guinea. The American base became US Advanced Sub Base A on 21 April 1943, US Advance Base A on 14 August and US Base A on 15 November. Its Australian counterpart, the Milne Bay Base Sub Area, was formed on 14 June 1943. Two coastal guns with searchlights were provided to protect the base from naval threats. New roads were built and the existing ones upgraded to make them passable in the wet conditions. A meteorological record was set on 29 April 1944, when of rain fell in a 24-hour period. By June 1944, there was over of road in the area.
