 After the war delaying resistance by the Soviet occupation forces as well as claims raised by West Germany to the former "Reichsautobahn" assets obstructed the resumption until 1954.Construction started in the US-occupied zone of Salzburg and Upper Austria, partly relying on the pre-war planning, and were extended after the country gained full sovereignty by the 1955 Austrian State Treaty.The first section of the West Autobahn up to Mondsee was opened in 1958, by 1967 the route between Salzburg and Wien / Vienna was completed.