The Chesapeake & Ohio Canal National Historical Park preserves 184.5 miles of historic towpath along the Potomac River from Georgetown, D.C., to Cumberland, Maryland. The 14.5-mile segment from Great Falls to Seneca is one of the most historically rich and ecologically diverse sections of the entire canal corridor, running through Montgomery County suburban Maryland on a flat, crushed-limestone and compacted-gravel surface with less than 50 feet of total elevation change — making it the most accessible long-distance trail option in the Washington, D.C. metropolitan area.
The Great Falls end begins at Great Falls Tavern Visitor Center at 11710 MacArthur Blvd, Potomac, a National Park Service facility with restrooms, interpretive exhibits on canal history, and ranger staff. A $20 per-vehicle entry fee or America the Beautiful annual pass is required at this end; access from the Seneca/Riley's Lock end is free of charge. Along the route, hikers and cyclists pass numbered canal locks, restored lockhouses (several available for overnight rental through the C&O Canal Trust), and the ruins of historic boat landings that document the canal's operation from 1831 to 1924.
The Violettes Lock area, approximately 8.5 miles from Great Falls (at canal mile 22.1 from Georgetown), features a restored lockhouse and quiet boat landing with views across the Seneca Creek confluence. At the Seneca terminus, Riley's Lock offers a historic stone lockhouse and lock structure adjacent to Seneca Creek wetlands — a significant habitat for great blue herons, osprey, bald eagles, and migratory waterfowl. Shorter out-and-back sections from either end are practical and rewarding; even a 1–2 mile walk from Great Falls reaches canal lock structures inaccessible by road.
Trail facts
- Trail area
- Potomac / Seneca (Montgomery County)
- Best season
- Year-round; spring wildflowers and fall color are highlights; can be muddy after rain
What to bring
- Comfortable hiking shoes or trail runners
- Water
- Snacks for full route
- Bug spray in summer
Location
Great Falls Tavern, 11710 MacArthur Blvd, Potomac, MD 20854
38.9993, -77.2510 View on map
Highlights
- Historic C&O Canal lock structures, lockhouses, and boat landings from the 1831–1924 operational era
- Violettes Lock (canal mile 22.1) — restored lockhouse with Seneca Creek confluence views
- Riley's Lock at the Seneca end — stone lockhouse adjacent to productive bird-watching wetlands
- Flat crushed-limestone towpath accessible to walkers, cyclists, and jogging
- Seasonal bird habitat: great blue herons, osprey, bald eagles, and migratory waterfowl
Tips for visiting
- Shorter out-and-back sections of 1–3 miles from Great Falls are rewarding without requiring the full 14.5-mile commitment
- Carry all water needed — no water fountains exist between the Great Falls Visitor Center and Seneca
- Bug spray is essential from May through August in the humid lowland towpath corridor
- The towpath surface becomes muddy after significant rainfall — trail runners or boots with traction improve comfort
- Access from the Seneca/Riley's Lock end avoids the $20 Great Falls vehicle entry fee
When to visit
Spring (April–May) brings canal-side wildflowers and peak bird activity; fall (October) offers foliage color reflected in the still canal water. Summer mornings are recommended for heat and insect avoidance — the towpath corridor is humid and shaded, with insects active from May through August.
Accessibility
The crushed-limestone and compacted-gravel towpath surface is largely accessible to wheelchairs and strollers on dry days, though muddy stretches after rain reduce usability. The Great Falls Visitor Center has paved, accessible routes to the canal level. This segment is one of the most wheelchair-accessible long-distance trail options in the Washington, D.C. region.
Frequently asked questions
Is the C&O Canal Towpath flat?
Yes — the towpath has less than 50 feet of total elevation change over the 14.5-mile segment from Great Falls to Seneca. It is one of the flattest long-distance trails in the Washington, D.C. region.
Can cyclists ride the towpath?
Yes. Cycling is permitted on the C&O Canal Towpath, and this segment is popular with cyclists. The crushed-limestone and compacted-gravel surface is passable on hybrid and mountain bikes.
Is there a fee to access the trail from the Seneca end?
Access from Riley's Lock and the Seneca area is free of charge. A $20 per-vehicle entry fee applies at the Great Falls Tavern end, or an America the Beautiful annual pass is accepted.
Are historic lockhouses available for overnight stays?
Yes — the C&O Canal Trust manages several historic lockhouses along the towpath available for overnight rental. Several are located near this segment; availability and booking details are on the Trust's website.
What wildlife is commonly seen along this section?
Great blue herons, osprey, bald eagles, white-tailed deer, river otters, beaver, and numerous migratory songbirds are regularly documented along the canal and Potomac River corridor.