In 1919, a seventeen-year-old San Francisco boy fell seriously ill. The second, and deadliest, wave of the Spanish Flu had reached the City. It struck down the young with particular cruelty.

The boy had always been a bit different–restless and fidgety and given to long rambles on Baker Beach and through the Presidio, but now, fevered and nearly skeletal, he developed a phobia. A very severe phobia of germs and people. He was sure that if he stayed in San Francisco he’d die. He begged his parents to let him visit Yosemite, a place he’d first visited when he was fourteen. The doctor advised against it, but the boy was so persistent that his parents eventually relented.

A month later, the boy, whose name was Ansel Adams, returned to San Francisco. His cheeks were tanned and his gauntness was gone. For the rest of the life, he credited Yosemite for his recovery. Nature became both his faith and his temple, and photographing it became his life’s calling.