Starting in the 1830s, migration from the eastern states westward went from a trickle to a flood. The rock formations at Muscle Shoals, AL made it one of the few places within hundreds of miles where the Tennessee River was shallow enough for people to cross. Originally, paths to the shoals had been worn by animals, and were later used by the native peoples for hunting and trading. As more people traveled on them, they became more prominent. One of the main routes to the west was the Natchez Trace, which ran through the shoals from Nashville, TN, to Natchez, MS.