In 1845 Thoreau leased some land owned by his friend and mentor,Ralph Waldo Emerson on Walden Pond near Concord,Massachusetts,and lived in a cabin on it for two years,two months,and two days.The experience gave Thoreau the chance to make keen observations on the world around him.The result became an American classic:Walden,which explores not only the soul of the searching Thoreau,but defines what it means to be a truly free person,and distills the essence of our relationship of Nature.