Itter Castle (Schloss Itter) is a 19th-century castle in Itter, a village in Tyrol, Austria. In 1943, during World War II, it was turned into a Nazi prison for French VIPs. The castle was the site of an extraordinary instance of the U.S. Army, German Wehrmacht, Austrian Resistance, and the prisoners themselves fighting side-by-side against the Waffen-SS in the battle for Castle Itter in early May 1945 before the end of the war in Europe.
The hill castle is atop a knoll at the entrance to the Brixental valley, about south of Wörgl and west of Kitzbühel.
A fortress at the site was first mentioned in a 1241 deed; previous constructions may have existed since the 10th century. The Brixental originally was a possession of the Prince-Bishops of Regensburg; the castle was an administrative seat of the Counts of Ortenburg in their capacity as Vogt bailiffs, and it also served to protect the Regensburg estates from incursions undertaken by the neighbouri