The Birnlücke (2,665 m (AA)) is the border pass at the western end of the Hohe Tauern mountains in Austria, between the Venediger Group and the adjoining Zillertal Alps. The border between Austria and Italy has run over the pass since 1919. The pass forms the border between the Austrian state of Salzburg and the Italian province of South Tyrol, the valleys of the Krimmler Achental and Ahrntal, and the Rieserferner-Ahrn Nature Park and Hohe Tauern National Park. Until the Schengen Agreement there used to be a regular border checkpoint at (2,634 m).