Parking at the Fellhorn Cable (fee 2002 was 2,50 Euros). Hike through Stillachtal up to Einoedsbach (preferably using a mountain bike). From Einödsbach a few minutes direction Waltenberger Haus. Before the Bacher Alp (hut) turn left to a very small and steep path leading up to Einoedsberg Alp and up to left side of Spaetengund Kopf. Follow the grassy ledges over Spaetengund Kopf and Wildengund Kopf. You will see the rest of the approach now. Proceed up to the left side of the snow and ice field directly beneath the north face of Trettachspitze. 2 1/2 up to 4 hours from parking, depending on bike usage.
Remark: you can also approach from the 'Waltenberger Haus' by traversing below the Maedelegabel northwest side.
Start a few meters left of the left end of the snow field. First pitch is a small water couloir (or use the face right of it, a bit more interesting). Second pitch leads up to the NE ridge itself. Good stand. Follow the ridge 2 lengths, a bit exposed. Then turn left to a small terrace ('Blodig Kessel')filled with scree. Best use the direct fissure to climb the final block leading to the summit. 1/2 to 2 hours from snow field, depending on rope usage. Rememer there is no easy hike down, so you have to climb back the NE ridge or (preferably) the NW ridge.
Rope (if needed), some slings and carabiners.
If you have information about this route that doesn't pertain to any of the other sections, please add it here.