Two Years Before the Mast is a book by the American author Richard Henry Dana, published in 1840, having been written after a two-year sea voyage starting in 1834. A film adaptation under the same name was released in 1946. In the book, which takes place between 1834 and 1836, Dana gives a vivid account of "the life of a common sailor at sea as it really is." He sails from Boston to South America and around Cape Horn to California. Dana's ship was on a voyage to trade goods from the United States for the Mexican colonial Californian California missions' and ranchos' cow hides.