Flexen Pass is a high mountain pass in the Austrian Alps in the Bundesland of Vorarlberg. It is at an elevation of 1,773 metres. It connects the upper Lech valley between Warth, Lech, and Zürs with the Klostertal near Stuben. The pass road was built in 1940 and leads to the road over the Arlberg pass. It became a necessity when the Arlberg railroad was opened in 1884. Before that, traffic mostly went over the Tannberg by way of Oberstdorf.