C&O Canal Hike 15

Dam 4 to Williamsport

This segment begins with a 4.7 mile roadwalk. While you can explore the next 1.4 miles or so of the towpath, repeated flooding and a landslide have made this detour mandatory even for those on foot. The roadwalk is actually very scenic, although traffic and narrow shoulders make the part along Dam Number 4 Road challenging. Your return to the towpath is dramatic, with the restored mill sitting by the Potomac just as it has since 1778. For the next 0.8 miles the Towpath passes beneath towering limestone cliffs at the upper end of "Big Slackwater". Caves dot the route here including the well known Howell Caves. At the inlet lock (41) the canal resumes and soon enters the half-mile long Dellinger Widewater. Past here, cliffs, often a hundred feet high, continue to near milepost 93. For a mile the towpath is a paved road through the summer home community of Falling Water. Soon the woods return and the Towpath passes through a quiet section to the village of Williamsport.


Trip Planner

Start: Dam 4
End: Williamsport
Miles: 16.4
Points of Interest: Dam 4, McMahon's Mill, Big Slackwater, Dellinger Widewater, Williamsport
Parking: Dam 4 (0.0 mi.), Lock 44 (15.9 mi.), Williamsport (16.4 mi.)
Water: Opequon Junction campsite, Cumberland Valley campsite, Williamsport (water at campsites normally turned off November-April)
Restroom or Privy: Dam 4, Opequon Junction campsite, Cumberland Valley campsite, Williamsport
Provisions: Williamsport
Camping: Opequon Junction campsite, Cumberland Valley campsite


Hike Data

Mile Navigation
0 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.
3.5 Dellinger Road, turn left.
3.9 Avis Mill Road, turn left.

McMahon's Mill. Cross canal and turn right on towpath.

7.5 Opequon Junction campsite.
11.8 Cumberland Valley campsite.
15.9 Lock 44.
16.4 Williamsport. Village comes right down to the canal. Within a few blocks find groceries, cafes and restaurants. Motels are located about 1 mile north on US 11. Visitor's Center in old Cushwa's building.

Explore the PHT

This village of about 2,000 has a long history. The land changed hands and names several times before it was formally laid out in 1786. In 1790 extra wide streets were built in an effort to be selected as the Nations Capital. President George Washington came here on October 14th of that year to discuss the proposal with town founder Otho Williams. The bid failed because the Potomac River was considered too shallow this far upstream for large ships. However for that day Williamsport was indeed the capital during President Washington's tour from Philadelphia to Washington, DC. During the canal's operating period, Williamsport was the center of canal life with many boats wintering here. Today Cushwa's Warehouse, right on the canal, has been restored as a visitors center containing exhibits and canal artifacts. The main streets feature quaint structures including Wolfe's On the Square. This store, filled with canal history is owned by the family of C&O boatman George "Hooper" Wolfe.

Last updated: April 10, 2015

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