Desert Solitaire is a collection of treatises and autobiographical excerpts describing Abbey's experiences as a park ranger and adventurer in 1956 and 1957. The opening chapters, First Morning and Solitaire, focus on the authors experiences of arriving at and creating a life within the Arches National Monument park. In this period the park is 'undeveloped' - road access and camping facilities are basic and there is a low volume of tourist traffic. Many of the books chapters are studies of the plants, animals and geography of the region around Arches National Monument. Serpents of Paradise and Cliffrose and Bayonets focus on Abbey's descriptions of the flora and fauna of the Arches area, and his observations of the already deteriorating balance of biodiversity in the desert due to the pressures of human settlement in the region. Abbey provides detailed inventories and observations of the life of desert plants and their unique adaptations to their harsh surroundings, including the pinyon pine, cliff-rose, sand sage and junipers. Abbey comments to the decline of the desert predators, particularly coyotes, mountain lions, bobcats and wildcats, and criticizes the role ranchers and the then policies of the Department of Agriculture have had in the removal of these animals, which in turn created unchecked growth in rabbit and deer populations and has damaged the delicate balance of the desert ecosystem. In these chapters and in Rocks, Abbey also goes at length to describe the geology he encounters in Arches National Monument, particularly the iconic formations such as Delicate Arch and Double Arch. In Water Abbey discusses the how the ecosystem adapts to the arid conditions of the Southwest, but also the springs, creeks and other stores of water to be found in the desert and in their own ways support some of the diverse but fragile plant and animal life. Some of the oddities of water in the desert, such as quicksand and flash floods are also explored. Abbey contrasts the natural adaptation of the environment to low water conditions with increasing human demands to create more reliable water sources. The Heat of Noon: Rock and Tree and Cloud describes the intensity of the summer months in the park, and the various ways in which animals and humans have tried to survive and adapt in those conditions.
Several chapters focus on Abbey's interactions with the people of the Southwest or explorations of human history. In Rocks Abbey examines the influence of mining in the region, particularly the search for lead, zinc, silver, and uranium. Abbey contrasts the difficult lives of the many who unsuccessfully sought their fortune in the desert whilst others left millionaires from lucky strikes, and the legacy of government policy and human greed that can be seen in the modern landscape of mines, shafts, towns and roads. Abbey offers the fable of one 'Albert T. Husk' who gave up everything and found his demise in the region in the elusive search of buried riches. In two chapters entitled Cowboys and Indians, Abbey describes his encounters with Roy and Viviano ('cowboys') and the Navajo of the area ('Indians'), finding both to be victims to of a fading way of life in the Southwest and in desperate need of better solutions to growing problems and declining opportunities. Abbey comments on some of the particular cultural artefacts of the region, such as the Basque population, the Mormons, and the Ancient Puebloan remains in cliff dwellings and stone petroglyphs and pictographs.
Several chapters centre around the Abbey's expeditions beyond the park, either accompanied or alone, often as vehicles for rich descriptions of the surrounding environments and other observations about the natural and human world in the region. Specifically, his search for a wild horse in the canyons (The Moon-Eyed Horse), his camping around the Havasupai tribal lands and his temporary entrapment on a cliff face there (Havasu), the discovery of a dead tourist at an isolated area of the Grand Canyon (The Dead Man at Grandview Point), his attempt to navigate the Maza area of the Canyonlands National Park (Terra Incognita: Into the Maze), and his ascent of Mount Tukuhnikivats (Tukuhnikivats, the Island in the Desert) are recounted. Down the River, the longest chapter of the book, recalls Abbey and an associate's journey by boat down the Glen Canyon, in part inspired by the original voyage of discovery undertaken by John Wesley Powell in 1869. Their journey is taken in the final months before its flooding by the Glen Canyon Dam, in which Abbey notes many of the natural wonders encountered on the journey will be inundated.
Finally, a couple of chapters are devoted largely to Abbey's reflections of the damaging impact of humans on the life, nature and culture of the region. Polemic: Industrial Tourism and the National Parks is an essay fiercely criticizing the policies and vision of the National Park Service, and the process by which developing the parks for automotive access has dehumanized the experiences of nature and created a generation of lazy and unadventurous Americans whilst permanently damaging the views and landscapes of the parks. In Episodes and Visions, Abbey meditates on religion, philosophy and literature and their intersections with desert life, as well as a collecting various thoughts on the tension between culture and civilization, espousing many tenets in support of environmentalism. In Bedrock and Paradox, Abbey details his mixed feelings about his return to New York after his term as a ranger has finished, and the paradoxical feelings encountered between the desire to solitude and the desire for community. Abbey also describes his difficulty in feeling he truly understands the desert, finding language, faith and philosophy fail to adequately capture its nature and its effect on the soul.