In Walden, Thoreau details his experiences of living in a cabin he built near Walden Pond. He explains the reasons behind his decision, and what he wanted to gain from the experience. We learn that this was an attempt to engage in a social experiment, and return to a simple life of self-reliance. Thoreau lived in this cabin for two years, mostly on his own.
However, we also learn that after this time, he started feeling that his time there had been enough. He claims that he started falling into an easy routine, and that it was necessary for him to pull himself out of it, as he had several lives to live and could not spare any more time on that particular one. He decided he needed to go back to society, and not escape it anymore.