During which event did East Germany halt access to West Berlin, necessitating airlifts?

The correct answer is the Berlin Airlift, which refers to the series of operations carried out between 1948 and 1949 when the Soviet Union blocked all ground routes into West Berlin. This blockade was initiated in response to the Western Allies' decision to introduce a new currency in West Germany, and it aimed to force the Allies out of the city. In response, the United States and its allies organized the Berlin Airlift to supply West Berlin with food, fuel, and other essential goods by air.

The significance of this event lies in its demonstration of the tensions of the Cold War and the commitment of the West to sustain West Berlin in the face of Soviet pressure. The airlift successfully delivered approximately 2.3 million tons of supplies to the residents of West Berlin, allowing them to survive despite the blockade.

While the Berlin Crisis is associated with this time period and the construction of the Berlin Wall further escalated tensions, neither directly pertains to the initial blockade of access to West Berlin through land routes. The Berlin Wall itself was erected in 1961, well after the airlift. Therefore, acknowledging the historical context and significance helps clarify why the Berlin Airlift is the most accurate answer to the question.