Barbed Wire Sunday

At midnight, the police and units of the East German army began to close the border and, by Sunday morning, 13 August, the border with West Berlin was closed. East German troops and workers had begun to tear up streets running alongside the border to make them impassable to most vehicles and to install barbed wire entanglements and fences along the 156 kilometres (97 mi) around the three western sectors, and the 43 kilometres (27 mi) that divided West and East Berlin. The date of 13 August became commonly referred to as Barbed Wire Sunday in Germany.