The headwaters of the Menzenschwander Alb lie on the southern slope of the Feldberg mountain range in the Landkreis of Breisgau-Hochschwarzwald. The Bernauer Alb rises on the southern slope of the Herzogenhorn. The Menzenschwander Alb is about long and flows south-east past Menzenschwand. The Bernauer Alb is about long; it also flows south-east, past Bernau. The confluence of the two headwaters is at Glashofsäge, about from Sankt Blasien.