At the end of summer 1839, the light changing and autumn in the air, Henry David Thoreau and his brother John clambered into their 15-foot-long homemade boat on an adventure north. They traveled the rivers from Concord, Massachusetts, to Concord, New Hampshire. Henry was two years out of Harvard, and his brother John was a few years older. They wound their way up the Concord and Merrimack Rivers by day and camped along the shores at night. This book, Thoreau's first, ribbons through and around that journey, describing their travels, and musing on history, literature, philosophy, the environment, politics, and the essence of the natural world. The book is also an elegy to his brother-companion on the journey and his best friend-who died a few years after, and whose presence is felt throughout.