The Boone's Lick Road or Boonslick Trail was an early 1800s transportation route from eastern to central Missouri in the United States. Running east–west on the north side and roughly parallel to the Missouri River the trail began in the river port of St. Charles. The trail played a major role in the westward expansion of the United States and the development of Missouri's statehood. The trail's eventual terminus at Franklin was the start of the better-known Santa Fe Trail. First traced by the sons of Daniel Boone, the path originally ended at a salt lick in Howard County used by the pair to manufacture salt. Today the lick is maintained as Boone's Lick State Historic Site.