This rugged terrain also offers challenging rockclimbing opportunities for experienced adventurers on three Billy Goat Trails . The most well-known access point to this area of the Park is at Great Falls Tavern , where guests can find mule-drawn canal boat rides , a small museum inside an historic tavern , and Great Falls Overlook , which provides easy access to spectacular views of the falls . Great Falls charges an entrance fee , but all other entry points to the C & O Canal National Historical Park are free .
Long before English settlement , Indigenous groups fished from the waters of the Potomac , as have generations of Americans since , including President Grover Cleveland . Pennyfield Lock at mile marker 19.6 was a particular favorite of Cleveland ’ s in the 1870s . He would stay at the Pennyfield Inn to escape the pressures of the Oval Office , catching bluegill , sunfish , large-mouth bass , and eel from the riverbank .
Left : Pennyfield Lock near mile marker 19 ; below : blue heron perches on rocks at the Widewater area of the C & O Canal .