I once saw the top of Mt. St. Helens (c 10,000') from the top of Mt. Adams (c 12,000'). That was when St. Helens still had a top. Mt. Rainier (14,000') proved beyond me, however (maybe if our amateur guide hadn't forgotten how to get around the back side of Gibralter we might have made it. But looking down of the top of Nisqually Glacier from a quarter mile up didn't encourage experimentation.) Ever seen an avalanche up close, or jumped over a crevasse? Looking down, it's white at the top, turns greenish further down, then to blue-black, then just black. It's a little nerve racking the first time.