This dissertation examines American literary travel writing published from 1835-1862, a period during which changing environmental and social conditions began to reshape traditional narrative forms. While the modern tourism industry began to emerge, ushering in a proliferation of travel writing in books, periodicals, and guidebooks, some authors considered the more disturbing or unsettling elements of travel, experimenting with digressions, fragmentation, shifts in genre, and surprising breaks in readers' expectations in order to depict and to enact a disturbance to one's more established sense of the world. In doing so, they confronted the disconnect between established ways of writing and thinking about travel and the realities of Indian Removal, environmental degradation, and American expansion. Henry David Thoreau and others came to call these experiments excursions, a newly reimagined narrative form which came to shape both literary writing and actual experience. Examining works by Thoreau as well as Washington Irving, Margaret Fuller, George William Curtis, and George Copway, among others, I identify in the excursion form a distinctive pattern in which the traveler departs from home, encounters some unexpected and surprising situation, and then returns with a new sense of the wider world, and often with a new sense of home, too. By considering such texts today, readers and scholars can begin to understand how literary practices might come to reshape our present understanding of the world, including the dramatic social and environmental changes attributable to climate change, human migration, and globalism. To that end, this dissertation concludes by examining twenty-first century writing by Barry Lopez, in which the excursion form offers a vital starting point for considering nonfiction literatures of the Anthropocene.