Discovery and name
Geography and exploration
Andrus has a 4.5 km-wide caldera at its summit. Weak fumarolic activity was detected in 1977 at Mt. Kaufmann in the northern end of the Ames Range of which Mt. Andrus is the southernmost volcano.
Mount Andrus was reportedly climbed by Michael J. Andrus (no relation to Carl H. Andrus) in August 2006 for the purpose of downhill skiing, which would make him the first Andrus to visit the mountain (though perhaps not the last). Carl H. Andrus is himself an avid mountain climber, having summited all 46 of the Adirondack high peaks and having, in his youth, climbed the Matterhorn.