In the nineteenth century, the fastest and easiest means of transport was by water. Riverways linked major United States cities with posts on the frontier. The Missouri and Mississippi Rivers, and their tributaries were highways of commerce to St. Louis, Missouri, and the port of New Orleans, Louisiana.
Bull boats, keelboats, skiffs, mackinaws, canoes, and steamboats carried travellers and cargo to and from Fort Union. Supplies for the Fort came up river and furs went down to make their way to the markets of the world.