The Four Power Agreement on Berlin ( September 1971 ) and the Transit Agreement ( May 1972 ) , helped to ease the tensions over West Berlin and made it a little easier for West Berliners to travel to East Germany and for Germans traveling along the road routes into the city instead of flying . The Four Power Agreement on Berlin ( September 1971 ) and the Transit Agreement ( May 1972 ) helped to slightly ease tensions over the status of West Berlin . While many restrictions remained in place , it also made it easier for West Berliners to travel to East Germany and it simplified the regulations for Germans traveling along the autobahn transit routes .