Waterloo, one of Alabama's oldest incorporated towns, was an important Tennessee River port during the steamboat era. In low-water season, after large boats from Louisville, Cincinnati, and other places downriver unloaded there, smaller craft transported goods and passengers upriver to Florence at the foot of the Muscle Shoals. Following a disastrous flood in 1847, the town was moved from its location on the riverbank, now under Pickwick Lake, to present higher ground. Union gunboats shelled it in July 1862, and Gen. William T. Sherman crossed the river there in November 1863 and made temporary headquarters in Dr. O.B. Sullivan's home.