C&O Canal Hike 14

Lock 38 to Dam Number Four

Above Lock 38 the canal passes beneath beautiful cliffs for about four miles. This area contains a number of caves including the Killiansburg Cave where people from the area took refuge during the Battle of Antietam. Further west, farmland returns and a peaceful walk takes you past the village of Mercersville, through the "Big Woods" and on to trip's end by the winch house next to Dam 4.


Trip Planner

Start: Lock 38 at Shepherdstown
End: Dam 4
Miles: 11.6
Points of Interest: Shepherdstown, Barron's C&O Museum, Mercersville (Taylor's Landing), Dam 4
Parking: Lock 38 (0.0 mi.), Snyder's Landing (4.2 mi.), Dam 4 (11.6 mi.)
Water: Killiansburg Cave campsite, Horseshoe Bend campsite, Big Woods campsite (water at campsites normally turned off November-April)
Restroom or Privy: Killiansburg Cave campsite, Horseshoe Bend campsite, Big Woods campsite, Dam 4
Provisions: Shepherdstown, Barron's Museum (limited snacks on weekends)
Camping: Killiansburg Cave campsite, Horsehoe Bend campsite, Big Woods campsite


Hike Data

Mile Navigation
0 Lock 38 at Shepherdstown - to reach town follow trail from parking lot which climbs to road. Turn left and cross Rumsey Bridge over Potomac. Town is just across the river. Bookstores, bakeries, restaurants and shops all found here. Motels and B&B's available.
2.4 Killiansburg Cave campsite.
3.9 Snyder's Landing.
4.0 Barron's Museum, located across road from canal. Open on weekends throughout the year.
7.1 Horsehoe Bend campsite.
8.1 Taylor's Landing (Mercersville), no services here.
9.7 Big Woods campsite.
11.6 Dam 4 and winch house. This is the only winch house remaining on the canal. The winch is used to lower the stop gate to prevent flooding. Mandatory 4.7 mile detour west to McMahon's Mill begins here. Cross canal, turn right and follow road uphill. Turns on detour are marked.

Explore the PHT

Dam 4
This area features the only remaining winch house on the canal. Its purpose was to lower a stop gate (similar to the one at Great Falls) if flooding occurred upstream. The dam overlook makes a fine picnic spot and serves as an entry to the "Big Slackwater" area. For 3.3 miles upstream from the inlet lock no canal was built. Instead, boats used the calm or slackwater section of the Potomac until they re-entered the canal above McMahon's Mill. For 1.3 miles above Dam 4 the towpath has been routed onto a service road. However beyond this point the towpath gets much rougher and has been closed above the inlet lock where the slackwater area begins. Repeated floods and a landslide have left the area ahead impassible. Take a minute to take in this peaceful and unique scene.

Note: Westbound hikers MUST take a 4.7 mile detour that begins by the winch house leading them back to the canal at McMahon's Mill. Detour begins by crossing canal, turning left and following road uphill. Turns on detour are marked.

Last updated: April 10, 2015

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Contact Info

Mailing Address:

Potomac Heritage National Scenic Trail
c/o Chesapeake and Ohio Canal National Historical Park
142 W. Potomac St.

Williamsport, MD 21795


This phone will reach the main line for the C&O Canal National Historical Park.

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