The Underhill Couloir above the Palisade Glacier is a key part of his 1931 first ascent route on Thunderbolt Peak .
The Underhill Couloir above the Palisade Glacier is named in his honor .
The Underhill Couloir above the Palisade Glacier is a key part of his 1931 first ascent route on Thunderbolt Peak , and is named in his honor .