For many people images of the major national parks in th US exist in the mind's eye as Ansel Adams photographs. A dedicated environmentalist as well as renowned artist, he was one of the 20th century's most ardent champions of the parks system. Through his photos, essays and letter-writing campaigns, he helped create new parks and better protect existing ones. He worked in more than 40 national parks over 50 years - including Shenandoah, the Great Smoky Mountains and Acadia in the East - and his work in the California High Sierra resulted in some of the most indelible images of the natural world ever made with a camera. 50 of the images in this volume have not been published in any authorized Ansel Adams book previously; many more are rarely seen. A substantial essay by photographic critic and historian Richard B. Woodward lays out Adams' significant role tracing the history of American conservation. The selection of photographs was made by Andrea G. Stillman, Adams' assistant late in life and a foremost expert on his work. A group of thumbnail images with brief narratives, enlivened by quotations from Adams, appears at the back of the book.