South of Konkordiaplatz, the glacier runs towards the valley of the Oberwallis (Upper Valais); on the east side, near Bettmeralp, lies a small glacier lake, Märjelensee (2,301 m (7,549 feet)); from the western side used to enter the Mittelaletschgletscher, but since the end cof the 20th century the connection with the Aletsch Glacier has been lost. Further down, until about 1880, the Oberaletschgletscher did also enter the Aletsch Glacier at its mouth. But since then both glaciers have been retreating so far that they do not connect anymore (the Upper Aletsch Glacier did retreat about 1.3 km (0.81 mi) from its connecting point with the Aletsch Glacier), but both serve now only as the source of the river Massa.