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C & O Canal Towpath: Antietam

C & O Canal Towpath: Antietam, Washington County, MD, 63.93 miles

Trail Facts

Length 64 mi
Elevation 263 to 416 ft
Grade 0.1% average
Shade cover 78%
Primary surface Dirt
Secondary surface Crushed gravel

Activities

E-biking · Biking · Walking · Running · Hiking · Birding · Kayaking · and more

About This Trail

The Antietam segment carries the towpath sixty-four miles from Harpers Ferry to Hancock, through the Great Valley and past some of the most fought-over ground in the country. The riding is rail-grade flat on hard-packed dirt, gaining only about two hundred feet end to end. Shepherdstown, Williamsport and Hancock sit along the way, and Fort Frederick State Park and the Antietam battlefield lie just off the path. At Big Slackwater the canal ran in the river itself, and the rebuilt towpath there hugs the cliff on concrete. The Piedmont segment continues east from Harpers Ferry and the Paw Paw segment runs west from Hancock.

RailTrailWx TIPS

C & O Canal Towpath: Antietam

Your comfort. Prognosticated.

  • This is the most heavily shaded of the three segments, so the towpath stays cool on hot afternoons and holds moisture after rain.
  • The towpath between mileposts 84 and 89, the Big Slackwater reach, can be under water when the Potomac runs high. That stretch is the one to check before you start.
  • The corridor holds an east southeast to west northwest line, so a west wind is a headwind toward Hancock and a tailwind coming back.
  • Cold air settles into the canal bed on clear nights and fog forms over the river and the slackwater pools, so early starts here are often damp and chilly.
  • Well water at the hiker-biker campsites needs filtering or boiling, and the park shuts it off from mid November to mid April.
  • The Western Maryland Rail Trail runs paved and parallel for much of the stretch near Hancock, which is a good alternative when the towpath is soft.
  • Barely two hundred feet of elevation separate Harpers Ferry from Hancock, so plan around wind, mud and daylight rather than climbing.

-Cory

Trivia

  • At Big Slackwater the canal company used the pools behind Dam 4 and Dam 5 instead of digging a canal, because rocky cliffs left no room.
  • Two floods in 1996 washed the Big Slackwater towpath away and forced riders onto a five mile road detour for more than fifteen years.
  • The rebuilt towpath there reopened in October 2012 and cost more than nineteen million dollars.
  • Killiansburg Cave, on the towpath itself, sheltered Sharpsburg townspeople during the Battle of Antietam on September 17, 1862.
  • On April 29, 1920 the berm wall of the Conococheague Aqueduct at Williamsport collapsed and dropped a canal boat into the creek below. The boat captain called for his tow boy to unhitch the mules and leapt onto the parapet as the wall gave way. A timber wall patched the break, and it was still standing when the canal closed four years later.
  • The restored Conococheague Aqueduct is the only watered, operational masonry canal aqueduct in North America.
  • Fort Frederick, built in 1756, is the only stone fort a British colony raised during the French and Indian War.

Climate

Excellent biking days per month, 2011-2025 climatology

In a typical year the C & O Canal Towpath: Antietam has about 121 to 166 days of excellent weather for popular activities such as hiking, dog walking, birding, e-biking, running, biking, and walking, with April, May, and October the best months.

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Hourly comfort scores for the next 15 days of weather, tuned to your activity and your own thresholds.

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Enjoy the C & O Canal Towpath: Antietam!

Peak Fall Color Climatology

Calendar of the typical peak fall color window along this trail

In half of past years, color along the C & O Canal Towpath: Antietam peaks October 24 to November 3, typically around October 29. The trail has 34% deciduous coverage, with the majority being white oak, chestnut oak, yellow-poplar, red maple, and black oak.

History

George Washington founded the Potowmack Company in 1785 to make the Potomac navigable. It built five skirting canals around the worst falls, good for floating down but not for hauling up. Its holdings passed to the Chesapeake and Ohio Canal Company in 1824. President John Quincy Adams turned the first spadeful on July 4, 1828. The Baltimore and Ohio Railroad broke ground the same day, and the two fought in court over the narrow riverbank between Point of Rocks and Harpers Ferry before agreeing to share it. The canal reached Cumberland on October 10, 1850, and five boats brought down 491 tons of coal that first day. The railroad had beaten it there by eight years, so the canal stopped at Cumberland and never crossed the Alleghenies. Mules towed the boats, often driven by children, and seventy-four lift locks raised them 605 feet above tidewater. An 1889 flood forced the company into receivership, and the railroad came to control it through its bonds. The March 1924 flood ended navigation. The United States acquired the canal in 1938. Justice William O. Douglas walked the whole towpath in March 1954 to stop a proposed parkway, and Congress made it a National Historical Park on January 8, 1971. This segment runs from Harpers Ferry through Shepherdstown and Williamsport to Hancock. At Big Slackwater the cliffs left no room for a canal, so boats ran in the river behind Dam 4, and that towpath was rebuilt on concrete and reopened in October 2012.

Trailheads

  • Harpers FerryMILE 0Directions
  • Lock 34MILE 0.9Directions
  • Dargan BendMILE 4.2Directions
  • Mountain Lock: Lock 37MILE 6.4Directions
  • AntietamMILE 8.9Directions
  • Shepherdstown: Lock 38MILE 12.2Directions
  • Snyders LandingMILE 16.2Directions
  • Taylors LandingMILE 20.4Directions
  • Dam 4MILE 23.8Directions
  • Big SlackwaterMILE 24.9Directions
  • McMahons MillMILE 27.6Directions
  • WilliamsportMILE 39.2Directions
  • Dam 5MILE 46.3Directions
  • Four LocksMILE 48.3Directions
  • McCoys FerryMILE 49.9Directions
  • Fort Frederick State ParkMILE 51.9Directions
  • Big PoolMILE 56.6Directions
  • Locks 51 and 52MILE 62.3Directions
  • HancockMILE 63.9Directions

Connects To

Western Maryland Rail Trail · Appalachian Trail · Potomac Heritage National Scenic Trail

Managed By

National Park Service, Chesapeake and Ohio Canal National Historical Park

Further Reading

  • National Park Service · Bicycling
  • National Park Service · Towpath Resurfacing Project
  • National Park Service · Chesapeake & Ohio Canal National Historical Park
  • National Park Service · Camping
  • National Park Service · Animals
  • National Park Service · The Chesapeake and Ohio Canal: The Kids Who Worked the Canal
  • Chesapeake and Ohio Canal Trust · Canal Groundbreaking
  • National Park Service · Big Slackwater Towpath Restoration
  • Chesapeake and Ohio Canal Trust · Big Slackwater
  • Chesapeake and Ohio Canal Trust · Sharpsburg
  • Chesapeake and Ohio Canal Trust · History of the Conococheague Aqueduct
  • National Park Service · Experience the Only Restored Operational Masonry Canal Aqueduct in North America
  • Maryland Department of Natural Resources · Fort Frederick State Park
  • National Park Service · Frequently Asked Questions
  • National Park Service · Canal Flood Information
  • Wikipedia · Chesapeake and Ohio Canal
  • Wikipedia · Chesapeake and Ohio Canal National Historical Park
  • National Park Service · Current Park Conditions

Nearby trails

Western Maryland Rail Trail

28 mi·MD
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C & O Canal Towpath: Paw Paw

60 mi·MD
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C & O Canal Towpath: Piedmont

60 mi·MD
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