Chesapeake and Ohio Canal National Historical Park: Downstream from McMahon's Mill (Blog Hike #956)

Trail: Chesapeake and Ohio Canal Towpath
Hike Location: Chesapeake and Ohio Canal National Historical Park, McMahon's Mill
Geographic Location: downstream from Williamsport, MD (39.53085, -77.82433)
Length: 4.2 miles
Difficulty: 3/10 (Easy/Moderate)
Date Hiked: September 2023
Overview: An out-and-back on an old canal towpath along the Potomac River.
Park Information: https://www.nps.gov/choh/index.htm
Hike Route Map: https://www.mappedometer.com/?maproute=946348
Photo Highlight:

Hike Video:

Directions to the trailhead: In western Maryland, take I-81 to SR 63 (exit 1).  Exit and go south on SR 63.  Drive SR 63 south 3 miles to Dam #4 Road and turn right on Dam #4 Rd.  Drive Dam #4 Rd. south 0.8 miles to Dellinger Road and turn right on Dellinger Rd.  Drive Dellinger Rd. west 0.5 miles to Avis Mill Road and turn left on Avis Mill Rd.  Avis Mill Rd. deadends at the McMahon's Mill Recreation Area, where this hike begins.

The hike: Stretching for 184.5 miles, the Chesapeake and Ohio Canal provided waterway transportation along the Potomac River between Georgetown, Washington D.C. and Cumberland, Maryland.  Construction of the canal began in 1828, but the canal did not reach Cumberland until 1850, which was 8 years after the famous Baltimore and Ohio Railroad reached Cumberland.  The canal's name came from a planned westward extension over the Allegheny Mountains and down the Youghiogheny and Monongahela Rivers to the Ohio River at Pittsburgh, PA.  That extension was never built due to cost and the railroad.

            Despite its relatively late construction, the canal proved useful for transporting coal downriver from Pennsylvania and West Virginia coal fields to Washington and the eastern seaboard.  The canal operated until 1924, when a major flood damaged the canal and forced it to close.  The federal government purchased the damaged canal remnants in 1938, and in 1961 President Eisenhower created a national monument to preserve what remained of the canal structures.

            Today Chesapeake and Ohio Canal National Historical Park is the most visited national historical park in the national park system.  The canal's towpath was converted to a bike path by 1960, and primitive campgrounds located at regular intervals allow bikers and hikers to travel the towpath's full length.  One of the towpath's more interesting and scenic sections is the portion immediately downstream from McMahon's Mill along a deep and broad section of the Potomac known as the Slackwaters.  Such is the portion of the bike path described here.

McMahon's Mill trailhead

            Start by walking around the red barn-like structure at the rear of the parking lot, heading for the Potomac River.  The wooden barn-like structure is actually the old McMahon's Mill, which generated electricity until 1922 when it was damaged by a flood.  The other side of the building features the old mill wheel, and more stone structures related to the old mill stand between the wooden structure and the river.  Take some time to examine these structures, read the interpretive signs, and imagine what this area might have been like in the early 1900's.

Stone mill structures

            When you get to the river, the Chesapeake and Ohio Canal Towpath Trail goes left and right.  Turn left to begin heading downstream with the Potomac River on your right.  Almost immediately you pass mile marker 88; the Towpath Trail has distance markers at 1 mile increments.  The Potomac River is broad and calm here, thus earning this area the name Slackwaters.  Fantastic views open up across the river into West Virginia.

Potomac River

            At only 0.2 miles, you reach the first of many concrete walkways that elevate the Towpath Trail over the edge of the river.  These walkways are necessary because vertical sandstone cliffs come almost to the river's edge on the left, thus leaving insufficient room for a bike path to get through.  The combination of rock and water makes the Slackwaters a very scenic area.

Elevated concrete walkways

            For the next 1.4 miles the trail surface alternates between raised concrete walkways and a gravel path.  The trail never strays more than a few feet from the Potomac, so any elevation changes are imperceptible.  Just shy of 1.5 miles, you cross the last raised concrete walkway.  Now the trail adopts a more traditional towpath appearance with a gravel trail surface.  Plenty of black walnut trees and some maple trees populate the riverside area, and lots of honeysuckle crowds the understory.

Towpath Trail below the Slackwaters

            Just past 2 miles into the hike, you reach mile marker 86.  Thus far one thing has been noteworthy in its absence from this canal towpath trail: a canal!  Along this part of the Chesapeake and Ohio Canal the boats were transported in the river itself, but in less than another 0.5 miles the old (separate) canal waterway reappears on the left.  The trail continues for another 86 miles, so you will need to turn around at some point.  The reappearance of the old canal is as good of a point as any.  Enjoy each Potomac River view one more time as you retrace your steps to McMahon's Mill to complete the hike.