Abendberg, one of the secondary elevations of the Bernese Alps, rising from the plateau of Interlachen or Bernese Oberland, in the canton of Bern, Switzerland, S. W. of the village of Interlachen, its northern base abutting on the lake of Thun. It rises about 3,500 feet above the plateau, and 5,300 above the sea level. Its southern slope is very fertile, and the lower portion heavily wooded. It is regarded as one of the most salubrious regions of the Alps. In 1842 Dr. Louis Guggenbuhl selected a site on the southern slope, several hundred feet below the summit, for an asylum for cretins, whom he hoped by careful treatment and the health-giving influences of the climate to restore to reason and healthful development. The institution did not accomplish all that was expected from it, and, after being maintained for 18 or 20 years, was on the death of its founder given up. (See Guggenbuhl, Louis.)