Fulda Gap
From 1815, the area appeared of minimal strategic importance, as it lay deep within the borders of the German Confederation and from 1871 of the German Empire. German military planning presumed any war would be effectively lost, long before an enemy reached that far into the homeland. The route became important again at the end of World War II when the U.S. XII Corps used it in their advance eastward in late March and early April 1945. The U.S. advance had little consequence for Germany's strategic position, which was hopeless by that point, but it allowed the Americans to occupy vast swaths of territory which the Yalta Conference of February 1945 had assigned to the Soviet occupation zone. This did much to compel the Soviets to honor the Yalta Conference agreement, meaning that Western Allies got access to Berlin. In exchange, the U.S. Army withdrew in July 1945 from Thuringia and Saxony, to the line agreed upon in Yalta.
During the Cold War, the Fulda Gap offered one of the two obvious routes for a hypothetical Soviet tank attack on West Germany from Eastern Europe, especially from East Germany. The other route crossed the North German Plain. A third, less likely, route involved travelling up through the Danube River valley through neutral Austria. The concept of a major tank battle along the Fulda Gap became a predominant element of NATO war planning during the Cold War. With such an eventuality in mind, weapons were evolved such as nuclear tube and missile artillery, the nuclear recoilless gun/tactical launcher Davy Crockett, Special Atomic Demolition Munitions, the AH-64 Apache attack helicopter, and A-10 ground attack aircraft.
Strategic location during the Cold War
The northern route through the Gap passes south of the Knüllgebirge and continues around the northern flank of the Vogelsberg Mountains. The narrower southern route passes through the Fliede and Kinzig Valleys, with the Vogelsberg to the north and the Rhön mountains and Spessart mountains to the south. More importantly, on emerging from the western exit of the Gap, encounters flat terrain from there to the river Rhine, which would have counted in favour of Soviet attempts to reach and cross the Rhine before NATO could prevent this. The intervening Main River would have been less of an obstacle.
The Fulda Gap route was less suitable for mechanized troop movement than the North German Plain, but offered an avenue of advance direct to Frankfurt am Main. Furthermore the capital of the Federal Republic in Bonn, was situated only 200 km to the west. A rapidly advancing Soviet or Warsaw Pact attack through the Fulda Gap, along the lines of Seven Days to the River Rhine, could have also potentially cut the territory of West Germany in two parts, making the long-term existence of a West German state untenable.
Strategic responses to the geographic feature
Strategists on both sides of the Iron Curtain understood the Fulda Gap's importance, and accordingly allocated forces to defend and attack it. The defense of the Fulda Gap was a mission of the U.S. V Corps. The actual Inner German border in the Fulda Gap was guarded by reconnaissance forces, the identification and structure of which evolved over the years of the Cold War.
From June 1945 until July 1946, reconnaissance and security along the border between the U.S. and Soviet zones of occupation in Germany in the area north and south of Fulda was the mission of elements of the U.S. 3rd and 1st Infantry Divisions. By July 1946, the 1st, 3rd, and 14th Constabulary Regiments, arranged from north to south, had assumed responsibility for inter-zonal border security, in an area that later became famous as the Cold War Fulda Gap. The U.S. Constabulary as a headquarters was subsequently drawn down.
Individual constabulary regiments were retitled armored cavalry regiments. This coincided with the 1951 upgrade of the U.S. Army's mostly administrative and occupation responsibilities in Germany to a combat army, via the arrival of four combat divisions from the United States. Thus, from 1951 until 1972, the 14th Armored Cavalry Regiment (ACR) patrolled the Fulda Gap. After the return of the 11th Armored Cavalry Regiment from Vietnam in 1972, the 11th ACR relieved the 14th ACR, and took over the reconnaissance mission in the Fulda Gap until the end of the Cold War.
The mission of the armored cavalry (heavy, mechanized reconnaissance units equipped with tanks and other armored vehicles) in peacetime was to watch the East-West border for signs of pre-attack Soviet army movement. The armored cavalry's mission in a war, was to delay a Soviet attack until other units of the U.S. V Corps could be mobilized and deployed to defend the Fulda Gap.
