"Desert Solitaire", Abbey's fourth book and first non-fiction work, was published in 1968. In it, he describes his stay in the canyonlands of southeastern Utah from 1956 to 1957. "Desert Solitaire" is regarded as one of the finest nature narratives in American literature, and has been compared to Aldo Leopold's "A Sand County Almanac" and Thoreau's "Walden". In it, Abbey vividly describes the physical landscapes of southern Utah and delights in his isolation as a back country park ranger, recounting adventures in the nearby canyon country and mountains. He also attacks what he terms the "industrial tourism" and resulting development in the national parks ("national parking lots"), rails against the Glen Canyon Dam, and comments on various other subjects.