Chesapeake and Ohio Canal National Historical Park | LOCK 36

Upstream view of Lock 36 at Mile 62.5 on the Chesapeake and Ohio Canal towpath

Upstream view of Lock 36 at Mile 62.5 on the Chesapeake and Ohio Canal towpath


Lock 36 is located just north of Harpers Ferry at Mile 62.5 on the C&O Canal towpath. It cannot be accessed by vehicle, so reaching it requires hiking or biking 2.4 miles (one way) downstream from the closest parking lot, the Dargan Bend Boat Ramp. See the Locks and Lockhouses web page for an interactive location map.


Lock 36 on the Chesapeake and Ohio Canal is now filled in with dirt, leaving only the tops of the retaining walls visible. This is a common practice for locks that are on the verge of collapse.

Downstream view of Lock 36 at Mile 62.5 on the Chesapeake and Ohio Canal towpath

Downstream view of Lock 36 at Mile 62.5 on the Chesapeake and Ohio Canal towpath

The current layout of the C&O Canal between Locks 34, 35, and 36 is very confusing. If you are heading downstream from Lock 37, while the canal obviously continues straight ahead towards Lock 35 (less than a tenth of a mile away), the towpath takes an unexpected sharp right-hand turn towards the Potomac River, leading far away from the lock and the canal. This is actually a service road, not the original towpath. If you want to see Lock 35 you must ignore this detour and continue straight along the original towpath, which is now a wide, grassy trail.

Path from Lock 36 to Lock 35 when heading downstream on the Chesapeake and Ohio Canal towpath

Path from Lock 36 to Lock 35 when heading downstream on the Chesapeake and Ohio Canal towpath

Once at Lock 35 you cannot go farther despite the fact that the canal still continues straight ahead. You must return to Lock 36 and take the detour. What has happened is that Lock 35 and an inlet lock just above Dam 3 (a stone’s throw away on the Potomac River) merge together in a V-shape, with the point of the V aiming downstream. The original towpath runs down the middle of the V and eventually comes to the point. With nowhere to go, it had to cross over either the inlet lock or Lock 35 via a footbridge to continue alongside the canal—it crossed over the inlet lock. The bridge is no longer there, and for whatever reason, the National Park Service chose not to rebuild it, instead opting for the service road detour. If you are traveling upstream from Lock 34, the detour veers towards the Potomac River just before Lock 35, completely bypassing it. The only way to reach it today is from Lock 36.

Dam 3 caused the Potomac River to pool behind it, and this ready-made water surplus was funneled into the canal through the inlet lock, which could be opened and closed to regulate the flow. This was the source of water for the canal from here all the way to Seneca. The inlet lock also let boats coming from West Virginia enter into the canal, thus drumming up additional business.

Today the inlet lock is plugged with stone at both the river end and the canal end to keep the waters of the Potomac out of the canal (the photo below shows the canal-end plug). The service road crosses the inlet lock over the river-end plug, making it the modern substitute for the original bridge. Why the National Park Service didn’t make the crossing over the canal-end plug and have the towpath continue on its original course is beyond me. My only guess is that the river-end plug was wider, thus allowing more room for hikers and bikers. But that’s just a guess.

Layout of the Inlet Lock and Lock 35 on the Chesapeake and Ohio Canal

Layout of the Inlet Lock and Lock 35 on the Chesapeake and Ohio Canal

Back to the Top


With a few exceptions, use of any photograph on the National Park Planner website requires a paid Royalty Free Editorial Use License or Commercial Use License. See the Photo Usage page for details.
Last updated on June 20, 2024
Share this article