This circular route requires a bit of advance training. After the climb via to the Felbertauern tunnel (shuttle service through the tunnel) there is a descent down to Mittersill which has plenty of twists and turns. Continue to Zell am See and Bruck. The climb to the Hochtor starts here, which exacts everything from even the best riders. The descent to Heiligenblut and the leisurely route through Mölltal provide the chance to recover, before the final climb to the Iselsberg starts, but the superb panoramic views are a reward for all your efforts.