High Quality Content by WIKIPEDIA articles! OZAV, The Prealpine Operations Zone was a Nazi German puppet district in the sub-Alpine area created in Italian territory during World War II. It was administered as part of the Reichsgau of Tyrol-Vorarlberg. The capital of the zone was Bolzano. OZAV was established on 10 September 1943 by the occupying German Wehrmacht, as a response to the Allied Armistice with Italy proclaimed two days earlier following the Allied invasion of Italy. It comprised the provinces of Belluno, Bolzano-Bozen and Trento.