On the way from Biel or from the Moosfluh in direction Alte Stafel and Aletsch forest you encounter scattered dry stone walls. Some are well preserved, others are slipped a bit downhill and fall gradually apart. Is this an old, long-forgotten trail? No, there are the remains of the "Riederfurka", an ancient water channel. Its last traces end at the Grossen Gufer, a rock glacier between Eggishorn and Bettmerhorn. The meltwater leaving in summer at the front of this rock glacier was caught and passed along the northern slope of the Bettmerhorn, beneath the Moosfluh and over the Härdernagrat to the Riederfurka. There the bisse "Riederfurka" divided into two branches. The water in the southern branch flowed towards Oberried. The northern branch led along the western slope of the Riederhorn, and its water flowed into the "Oberriederi", a suonen as well abandoned since long time. Unfortunately the age of "Riederfurka" is not known. Probably it was built at the end of the 16th century, when the "Oberriederi" had to be given up.