The Brandenberg Alps (German: Brandenberger Alpen) are a sub-group of the Northern Limestone Alps, that run in front of the Eastern Alps for their whole length. They lie entirely in Austria between Achensee in Tyrol, the Inn Valley and the Bavarian Prealps.They are widely known in German as the Rofangebirge, although the actual Rofan (also Sonnwendgebirge) is only the western part of the area between the Brandenberger Ache stream and the Achensee lake.