Large Format for easy reading. Renowned for having lived the doctrines of Transcendentalism, Walden, or Life in the Woods, recounts the two years and two months Thoreau spent at Walden Pond. Part memoir and part spiritual quest, this American classic emerged from a nine year process of composition and revision. Among his lasting contributions are his writings on natural history and philosophy, where he anticipated the methods and findings of ecology and environmental history, two sources of modern day environmentalism.