The anti-aircraft fortifications on the "Pig’s Back" (German: Batterie Schweinsrücken), built by the Germans between 1939 and 1944, formed a defensive complex protecting Klaipėda from air raids. The main structure of the fortifications was the battery, consisting of two main-caliber and three auxiliary-caliber gun platforms, interconnected by underground facilities. Several additional gun platforms were constructed separately. Nearby, bunkers were built to serve as a command post, crew quarters, an electric generator station, and an arsenal.