Great Falls Tavern and Lock 20 on the Chesapeake and Ohio Canal
Lock 20 and Great Falls Tavern are located at Mile 14.4 on the C&O Canal towpath. There is a fee to enter the Great Falls section of the park. Many large parking lots serve the area. See the Locks and Lockhouses web page for an interactive location map.
NOTE: Sections of the towpath, locks and other historical structures, trails, campgrounds, picnic areas, boat ramps, and visitor centers are constantly being closed due to damage and/or repair. When planning an adventure within Chesapeake and Ohio Canal National Historical Park, make sure the areas you plan to visit are open by checking the National Park Service’s official Current Park Conditions web page.
Lock 20 is undoubtedly the most visited lock on the Chesapeake and Ohio Canal for it is located right next to the Great Falls, the busiest location in Chesapeake and Ohio Canal National Historical Park. It has been restored and is one of the few functioning locks on the canal today.
Upstream gates of Lock 20 on the Chesapeake and Ohio Canal
The National Park Service used to offer mule-drawn canal boat rides that actually passed through the lock, but those have been discontinued for launch boat rides on the canal. The following are some photos from when the mule-drawn rides were being held.
Approaching Lock 20 at Great Falls Tavern, Chesapeake and Ohio Canal National Historical Park
Entering Lock 20 from downstream on the Chesapeake and Ohio Canal
Canal boat enters Lock 20 from downstream on the Chesapeake and Ohio Canal
Canal boat exiting Lock 20 on the Chesapeake and Ohio Canal
Great Falls Tavern started out as the lockhouse for Lock 20. It was built in 1828 when construction on the canal itself began. W. W. Fenlon, the lockkeeper in charge of Locks 15 through 20, suggested to the C&O Canal Company to build an inn, adding that he and his wife would run it. The inn portion of the building—the large three-story section that now houses the Great Falls Tavern Visitor Center—opened in 1831. The original lockhouse is the smaller building on the backside of the inn.
Great Falls Tavern, Chesapeake and Ohio Canal National Historical Park
Original lockhouse portion of Great Falls Tavern in Chesapeake and Ohio Canal National Historical Park
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Last updated on June 29, 2026
