Wolf's Lair (German: Wolfsschanze; Polish: Wilczy Szaniec) was Adolf Hitler's first Eastern Front military headquarters in World War II. The complex, which would become one of several Führerhauptquartiere (Führer Headquarters) located in various parts of occupied Europe, was built for the start of Operation Barbarossa – the invasion of the Soviet Union – in 1941. It was constructed by Organisation Todt.