Wolf's Lair (Wolfsschanze) was Adolf Hitler's first Eastern Front military headquarters in World War II. The complex, which would become one of several 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.
The top secret, high security site was in the Masurian woods about 8 km from the small East Prussian town of Rastenburg (now Kętrzyn). 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 Führer Begleit Brigade. Despite the security, an assassination attempt against Hitler was made at 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 the summer of 1944, work began to enlarge and reinforce many of the Wolf's Lair original buildings, however the work was never completed because of the rapid advance of the Red Army during the Baltic Offensive in autumn 1944. On 25 January 1945, the complex was blown up and abandoned 48 hours before the arrival of Soviet forces. The Red Army captured the abandoned remains of the Wolfsschanze on 27 January without firing a shot. It took until 1955 to clear over 54,000 land mines which surrounded the installation. Today only impressive concrete ruins exist.
The Walls of Constantinople are a series of defensive stone walls that have surrounded and protected the city of Constantinople (today Istanbul) since its founding as the new capital of the Roman Empire by Constantine the Great. With numerous additions and modifications during their history, they were the last great fortification system of antiquity, and one of the most complex and elaborate systems ever built. They were also the largest and strongest fortification in both the ancient and medieval world.
Initially built by Constantine the Great, the walls surrounded the new city on all sides, protecting it against attack from both sea and land. As the city grew, the famous double line of the Theodosian Walls was built in the 5th century. Although the other sections of the walls were less elaborate, they were, when well-manned, almost impregnable for any medieval besieger.