What was the name of the 1971 agreement that improved access to West Berlin?

The 1971 agreement that improved access to West Berlin was the Four Power Agreement on Berlin.

The United States, the United Kingdom, France, and the Soviet Union signed the agreement on 3 September 1971. These four powers retained special responsibilities for Berlin from the postwar occupation, so their agreement was essential to resolving disputes over the city’s status.

The accord confirmed that West Berlin was not a constituent part of West Germany while also recognizing its practical links with the Federal Republic. It established principles for reliable transit routes between West Germany and West Berlin and helped reduce tension after the Berlin crises of the late 1950s and early 1960s.

The agreement was followed by implementing arrangements, including the 1972 Transit Agreement. It did not remove the Wall, but it made life and travel for West Berlin’s residents more predictable during the remaining years of division.