The Wolf’s Lair may be the most famous example of Germany’s wartime presence in Masuria, but it’s not the only one. A second bunker complex, known as Mauerwald, was built 18km northeast of Hitler’s secret headquarters. The 30 bunkers and accompanying buildings, which were occupied from 1941 to 1944, were home to a handful of the Nazis’ top military commanders, including Field Marshall Paulus, General Guderian and Colonel von Stauffenberg.