Mapping the past—and the future—of American trails.In Trail Work, Dillon Osleger excavates the forgotten trails of the Western United States. He shows how one of the greatest infrastructure investments in the nation's history—paths through our public lands—has been rubbed away by time and deliberate neglect. Osleger unearths the wagon roads, water sources, trap lines, and Indigenous trading trails that once knitted the West together. He reveals centuries of path building, more than two-thirds of a nationwide network of trails and campgrounds, now erased from the map. Dwindling federal investment and privatized timber forests, ranches, and oil fields have blocked access to public lands, prompting to Osleger to ask: How can we better care for the places that are claimed for the American public, but are too often abandoned or sold? Osleger has trail eyes like no other from his years as a trail builder, geologist, professional mountain biker, and public lands advocate. Here he offers a land ethic born of joy in stewardship, attention to history and community, and living and cycling lightly. From the Central California Coast to the Sierra Nevada, out to Colorado and up to Washington, Osleger embarks on a wayfinder's journey, revealing an atlas of lost trails for everyone who loves the outdoors.