On Sunday morning, U.S. troops marched from West Germany through East Germany, bound for West Berlin. Lead elements—arranged in a column of 491 vehicles and trailers carrying 1,500 men, divided into five march units—left the Helmstedt-Marienborn checkpoint at 06:34. At Marienborn, the Soviet checkpoint next to Helmstedt on the West German-East German border, US personnel were counted by guards. The column was long, and covered from Marienborn to Berlin in full battle gear. East German police watched from beside trees next to the autobahn all the way along.