In Continental Divide, Maurice Isserman tells the history of American mountaineering through four centuries of landmark climbs and first ascents. Mountains were originally seen as obstacles to civilization; over time they came to be viewed as places of redemption and renewal. The White Mountains stirred the transcendentalists; the Rockies and Sierras pulled explorers westward toward Manifest Destiny; Yosemite inspired the early environmental conservationists. Climbing...