Whitewater Canal, Indiana, was included in the state's Internal Improvements Act of 1836. The canal started in Lawrenceburg on the Ohio River and originally ended at Cambridge City, on the Old National Road. Hagerstown merchants financed an extension to their town, making the canal 76 miles in length. Ohio also built a 25-mile spur linking Cincinnati to the canal.
Fifty-six locks were built to accommodate a fall of nearly 500 feet. After the state went bankrupt in the 1840s, the canal was completed by private owners. In 1862, the Indianapolis & Cincinnati Railroad purchased the canal, laying its tracks on the canal towpath. After the canal fell into disuse, it was used as a source of water power for many grist mills. The Metamora Grist Mill, now a state park, is an example. The state took over a 14-mile section of the canal in 1946 and operates a horse-drawn canal boat (the Ben Franklin III) and the mill at Metamora. Preserved at Metamora is the Duck Creek Aqueduct, a covered bridge that carries the canal 16 feet over Duck Creek. It is believed to be the only structure of its kind in the nation.