Mt. Washington

The age of Mount Washington is probably no more than a few 100,000 years, similar to that of other central High Cascade stratovolcanoes. During the late Pleistocene, cirques were excavated into the flanks of the summit cone by valley glaciers which extended more than 12 kilometers east and west. The is no evidence of recent reactivation of Mount Washington volcanism, but a series of aligned small basaltic andesite spatter cones erupted on the northeast flank approximately 1,330 years ago

This picture is taking from inside at the Dee Wright Observatory.