In July 1845, Henry David Thoreau built a small cottage in the woods near Walden Pond in Concord, Massachusetts. During the two years and two months he spent there, he began to write Walden , a chronicle of his coexistence with nature. Thoreau has an important place among naturalists, but Walden has also had an effect on the work of social reformers such as Martin Luther King, John F. Kennedy, Leo Tolstoy and Gandhi.