[Bilbo] used often to say there was only one Road; that it was like a great river: its springs were at every doorstep, and every path was its tributary. ‘It’s a dangerous business, Frodo, going out of your door,’ he used to say. ‘You step into the Road, and if you don’t keep your feet, there is no knowing where you might be swept off to.’ “

- Frodo Baggins, p. 83 of The Fellowship of the Ring (Houghton Mifflin)