Half a century ago a rag-tag group of innovators was building a foundation for modern American rock climbing from a makeshift home base in Yosemite. Photographer Glen Denny was a key figure in this golden age of climbing, capturing pioneering feats on camera while tackling challenging ascents himself. In entertaining short pieces enlivened by his iconic black-and-white images of Yosemite's big wall legends, Denny reveals a young man's coming of age...