The Berlin Blockade was one of the first major crises of the Cold War. During the occupation of post–World War II Germany, the Soviet Union blocked the Western Allies' (United States, France and Britain) railway, road, and canal access to the sectors of Berlin under Western control. The Berlin Blockade lasted 11 months. The blockade was broken by a massive U.S.-British airlift of vital supplies to West Berlin's two million citizens.