John Middendorf | Substack

John Middendorf

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Climber, Designer, Inventor of A5 and D4 climbing tools.

1.8K+ subscribers

Mechanical Advantage: Tools for the Wild Vertical

Mechanical Advantage: Tools for the Wild Vertical

By John Middendorf

The history of engineered tools for climbing and alpinism (and some environmental rambles). (Looking for D4 portaledges? See bigwalls.net)

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