Muscovites, mostly women because the males had joined the Narodnoe Opolchenie (Popular Regiments or People's Militia), dig anti-tank ditches outside of Moscow in October 1941. The first snows stopped the Germans until the ground froze, but in the meantime both the Soviets and the Germans wallowed in mud. Marshal of the Soviet Union Georgy K. Zhukov(December 1, 1896 - June 18, 1974) ordered Moscow's citizens to dig defenses. Zhukov's memoirs recount lightly dressed citizens leaving Moscow to dig anti-tank ditches, trenches, build obstacles and fill sandbags. He later wrote, "Mud stuck to their feet and to the wheels of their wheelbarrows in which they carried earth, unbelievably increasing the weight of the shovel, which even without mud, was not very handy for women." Still, the civilians constructed an elaborate defense perimeter under Zhukov's orders. According to Zhukov's biographer Otto Preston Chaney, around the Western approaches to the city, Muscovites emplaced or dug 201 miles (323.4 kilometers) of anti-tank obstacles and ditches, 158 miles (254.2 kilometers) of anti-infantry obstacles, and laid minefields. 3,800 prepared bunkers and fire bases were built. 37,500 metal "hedgehogs" were set up to stop vehicles. Wooden tank obstacles extended from Aleksandrovsk, in the Ivanovsk Region along a front of 860 miles. The obstacles were arranged from 54 yards (49.3 meters) deep to half a mile (0.8 kilometers), covering 205 square miles (531 square kilometers).