in the Dolomites, takes 3 days and 60 pitons, 5.9 and 3 aid sections. Most committing big wall climbing to date. 1935 : Fritz Wiessner and Roger Whitney, using only 1 protection piton, climb Vector, on Ragged Mountain, Connecticut, rated 5.8+ R, likely 5.9, the hardest pitch in the US for a decade. 1935 : Pierre Allain, added a rubber band to a tennis shoe as a climbing shoe; later, in 1947, with Edmond Bourdonneau (EB), he markets a stiffer, flat-soled edging shoe, the "PA". 1936 : and Ettore Castiglioni free climb, in two days, a 29-pitch route on the Marmolada, Dolomites, UIAA VII- (5.10c). Hardest long, totally-free climb in the world. 1937 : develops and sells the first leather boots with "lug-soled rubber" (called tank-tread) for rock climbing, mountaineering, and hiking; called "Vibram soles". 1937 : Emilio Comici re-climbs the North Face Dimai Route route on the Cima Grande alone, with some gear but no rope, mostly free-solo (5.9), but pulling on some pitons, in three and a half hours. 1938 : Riccardo Cassin, Gino Esposito, Ugo Tizzoni ascend, in 3 days, the classic, alpine, 3,500-foot Walker Spur of the Grandes Jorasses "...perhaps the finest in existence" Gaston Rébuffat. 1939 : David Brower and the rest of his Berkeley crew use four bolts in the process of ascending Ship Rock in New Mexico. 1940s 1940s : World War II leads to the development of inexpensive, army-surplus pitons, carabiners and the newly invented nylon rope, making leader falls significantly safer. 1945 : Chris Preston, after a top rope, leads, with no protection, the two pitches of Suicide Wall, in Ogwen, Wales, at E2 5c (5.10c X). 1946 : and Sepp Spiegl create an 8-pitch route on Fleischbank, Austria, UIAA VII (5.10d) with four hard pitches: VII, VII-, VI, VI-. 1946 : solves Marie-Rose, in Fontainebleau, France, considered one of the first-ever boulder problems. 1947 : Pierre Allain, in France, and Raffi Bedayn, in the US, market lightweight, aluminum carabiners for climbing, significantly reducing the weight carried by climbers. 1947 : , and Franz Lorenz lead a traditional climbing route Nordverschneidung, on , Austria, the world's hardest big wall climbing route at UIAA VII (21-pitches). 1949 : Harold Goodro leads Goodro's Wall, 5.10c, Big Cottonwood Canyon, UT, 80 feet. Hardest short climb in the USA. 1949 : Peter Harding leads, after a top rope, the traditional climbing route Demon Rib, at