Start this walk from the parking area by the toll booth in the Kelchsau valley right after the village of Kelchsau. From there, keep to the right and start walking into the Langer Grund valley. The route runs along the road, passing snow-covered forests, Now and then the tour leads along the river. After almost one hour walking time you get to the alpine inn Gasthaus Moderstock. Have a stop off there to warm up and enjoy the delicious traditional cooking. Then walk on into the valley for about one more half hour. Then you get to the mountain hut Erler Brennhütte, the destination of your tour.
In the late spring the road might already be open to the alpine pasture Tiefental Alm.
Get more details and a map from the tourist information office in Hopfgarten.