On June 8, 1867, he set sail on the pleasure cruiser Quaker City for five months, and this trip resulted in The Innocents Abroad or The New Pilgrims' Progress. In 1872, he published his second piece of travel literature, Roughing It, as an account of his journey from Missouri to Nevada, his subsequent life in the American West, and his visit to Hawaii. The book lampoons American and Western society in the same way that Innocents critiqued the various countries of Europe and the Middle East.