The Berlin Blockade occurred between 24 June 1948 and 12 May 1949. It was one of the first major escalations of the Cold War. After World War II, Germany was divided into four sections, each controlled by one of the Allied contries, US, France, Britain, and Soviet Russia. Since Berlin lay within the Soviet section, Berlin too was divided between the four Allies.
In 1948, the Soviets tried to gain complete control of Berlin by blocking all road and rail access to West Berlin. This was the Berlin Blockade.
The West’s answer to the Berlin Blockade was the Berlin Airlift, an audacious and ultimately successful plan to fly in, or airlift, all supplies, fuel and food, that were needed for the population of West Berlin.