Wolf's Lair (German: Wolfsschanze; Polish: Wilczy Szaniec) was Adolf Hitler's first Eastern Front military headquarters in World War II. The complex, which became one of several Führerhauptquartiere (Führer Headquarters) in various parts of eastern Europe, was built for the start of Operation Barbarossa – the invasion of the Soviet Union – in 1941. It was constructed by Organisation Todt.
The top secret, high security site was in the Masurian woods about 8 km (5.0 mi) east of the small East Prussian town of Rastenburg (now in Gierłoż, Kętrzyn County, Poland). Three security zones surrounded the central complex where the Führer's bunker was located. These were guarded by personnel from the SS Reichssicherheitsdienst and the Wehrmacht's armoured Führerbegleitbrigade. Despite the security, the most notable assassination attempt against Hitler was made at the Wolf's Lair on 20 July 1944.
Hitler first arrived at the headquarters on 23 June 1941. In total, he spent more than 800 days at the Wolfsschanze during a 3½-year period until his final departure on 20 November 1944. In mid-1944, work began to enlarge and reinforce many of the Wolf's Lair original buildings. The work was never completed because of the rapid advance of the Red Army during the Baltic Offensive in late 1944. On 25 January 1945, the complex was blown up and abandoned 48 hours before the arrival of Soviet forces.
The area was cleared of abandoned ordnance such as land mines following the war, and the entire site was left to decay by Poland's Communist government. The Wolf's Lair has been developed as a tourist attraction since the Fall of Communism in the early 1990s. Visitors can make day trips from Warsaw or Gdańsk. Hotels and restaurants have grown up near the site. Plans have periodically been proposed to restore the area, including the installation of historical exhibits.