The C&O (Chesapeake and Ohio) Canal was built between 1828 and 1850 and extended about 185 miles from Washington to Cumberland, Maryland. It generally follows the Potomac River, which cuts through the Appalachian mountains. The plan was to continue the canal so that it would link to tributaries of the Ohio River (hence the name), but by 1850 railroads had proved to be superior means of transportation, and the canal terminated at Cumberland. The canal operated until 1923 when one of the periodic floods caused too much damage to justify the cost of the repairs. Although there was a considerable amount of mule-pulled canal barge traffic, it was never profitable due to high maintenance expenses and competition from rail transport. The canal is now a National Historical Park under the auspices of the National Park Service. Many of the features have been perserved, and the long, but very narrow park, provides interesting glimpses of America during the industrial revolution.
The towpath has been preserved and reconstructed for the entire length of the canal. It is a popular location for walking, hiking, jogging, and bicycling. Due to damage to some of the aqueducts that carried the canal over rivers and streams flowing into the Potomac, the canal itself will never be completely restored. Some sections have been reconstructed and watered, most notably the twenty-two miles closest to Washington. During the spring and summer, tourists can take canal boat rides in the Georgetown area of Washington and at Great Falls, Maryland.