Helmstedt–Marienborn border crossing

The Border checkpoint Helmstedt–Marienborn (German: Grenzübergang Helmstedt-Marienborn), named Grenzübergangsstelle Marienborn (GÜSt) (border crossing Marienborn) by the German Democratic Republic (GDR), was the largest and most important border crossing on the Inner German border during the division of Germany. Due to its geographical location, allowing for the shortest land route between West Germany and West Berlin, most transit traffic to and from West Berlin used the Helmstedt-Marienborn crossing. Most travel routes from West Germany to East Germany and Poland also used this crossing. The border crossing existed from 1945 to 1990 and was situated near the East German village of Marienborn at the edge of the Lappwald. The crossing interrupted the Bundesautobahn 2 (A 2) between the junctions Helmstedt-Ost and Ostingersleben.

A checkpoint was established on the site on 1 July 1945, which was on the demarcation line between the British and Soviet occupation zones. Its scope included the interzonal railway traffic as well as the motor vehicle traffic on the Reichsautobahn between Hanover and Berlin. The checkpoint buildings were located directly on the zones' border, and consisted of little more than temporary wooden buildings.

The most important inner-German checkpoint, the Autobahn crossing at Helmstedt was named Alpha by the Western Allies. Its counterpart in the Berlin southern borough of Dreilinden was named Bravo. The connection between these checkpoints gained its importance from being the shortest connection between the western zones and Berlin, at 170 km (110 miles). During the Berlin Blockade, which endured from June 1948 to May 1949, the Soviet checkpoint was closed.

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