A file containing documents concerning travel by Allied officials to and from Berlin. The principal document in the file is an American report on the history, politics, and legal aspects of Allied access to Berlin. This report covers many aspects of the situation, including wartime and early postwar decisions; the Allied and Eastern positions; the Berlin air regime; rail and road access to the city; the effects of the 1971 Quadripartite Agreement; the "vulnerable point" of Allied access to East Berlin; and contingency planning for the interruption of Allied access to Berlin. Other subjects discussed in the file include the opening of the first section of the autobahn between Berlin and Hamburg; discussion as to who was entitled to use British Military Government identity cards; the issuing of second passports to British officials visiting East Germany; and the British government's position on the status of Berlin, under which the sector crossing was not recognised as an international frontier.