About John Middendorf
John William Middendorf IV was an American big wall climber, mountaineering writer and designer of climbing equipment. Middendorf decided to leave Yosemite in 1986 and founded A5 Adventures Inc., to design and manufacture portaledges in Flagstaff, Arizona. Based on his near-death experience, Middendorf's portaledge designs were among the first that could withstand the severe weather of high alpine destinations including the Himalayas and Karakoram. Also in the late 1980s and early 1990s, he pioneered numerous difficult big wall routes in Zion National Park. After graduation, he headed to Yosemite where he worked as a member of the search and rescue team, and pioneered many new routes.
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