Green Ridge Hiking Trail and C&O Canal Loop

Green Ridge State Forest and Chesapeake and Ohio Canal National Historical Park (near Flintstone and Little Orleans)

Green Ridge State Forest, in Allegany County, is Maryland’s second-largest state forest, according to the C&O Canal Trust, and the C&O Canal and Potomac River form its southern edge for about 17 miles. That shared border makes a long loop possible: a forest trail through the hollows one way and the canal towpath the other.

The National Park Service, in its 2015 Potomac Heritage Trail hike pages, describes “a 36-mile loop hike” using the Green Ridge Trail between Lock 58 and Lock 67 plus the towpath.

The hike

Trail names here have shifted over the years, so get the forest’s current map from headquarters first. The NPS says the Green Ridge Trail leaves the towpath at Lock 58 and rejoins it at Lock 67, with counts of 17.8 miles to “nearly 20 miles.” The current DNR trails page lists an 18-mile Great Eastern Trail with white blazes and says the trail system offers “50 plus miles of hiking trails” for day hikes or “multi-day backpacking experiences.” The Great Eastern Trail’s own Maryland page describes its western route leaving the towpath at Lock 58 on the Long Pond Trail and continuing on the Pine Lick Trail to Pennsylvania’s Mid State Trail.

Leonard Adkins, writing for Blue Ridge Outdoors in 2010, hiked the Green Ridge Hiking Trail 18.1 miles one way. Less than 2 miles in he reached a pool where Pine Lick meets Fifteenmile Creek, and he camped beside the Fifteenmile Creek ford at 4.5 miles. Later the trail drops to Big Run, with “many possible campsites close to the stream,” and ends at MD 51. He counts more than 60 stream crossings, 26 of them on Big Run alone, plus wading and swimming holes, and suggests summer, when serviceberries ripen.

The towpath half is flat and very different. The NPS calls the Little Orleans to Paw Paw stretch “the wildest, most beautiful and remote section of the Towpath.” Heading upstream from Lock 58, it passes Devils Alley, Stickpile Hill, and Sorrel Ridge hiker-biker sites, then the 3,118-foot Paw Paw Tunnel, which the NPS says is lined with bricks “six deep.” Bring a flashlight. Past the Paw Paw Tunnel campsite and Purslane Run, Lock 67 is where the forest trail returns to the towpath, with Town Creek campsite a few tenths of a mile beyond.

The NPS’s current conditions page notes a towpath stretch below Town Creek, roughly mile 156.9 to 160.1, was repaired and reopened May 26, 2026. For a shorter, towpath-only overnight through the tunnel, see Little Orleans to Paw Paw.

Tips

Register before you camp. Backpackers register at Green Ridge Headquarters with an itinerary listing everyone in the group.
Plan for wet feet. The forest trail fords streams dozens of times.
Treat all water, including C&O well water, which the NPS signs as non-potable.
Carry a flashlight for the Paw Paw Tunnel.
Don’t bring outside firewood. Buy it locally or gather it on site.
Call ahead for trail conditions at 301-478-3124.

Camping

In the state forest, the DNR says “Backpack camping is also permitted throughout the forest,” after registering at headquarters. Campfires are allowed except during drought, and Leave No Trace applies. The forest also has about 100 designated primitive sites, many near the Potomac and Fifteen Mile Creek, each with a picnic table and fire ring.

On the towpath, hiker-biker campsites are free, first come, first served, and limited to one night per trip, according to the NPS. Each has a chemical toilet, picnic table, fire pit, and well water that must be treated. Camp only in designated sites, and use only the fire rings or grills provided.

Inside Intel: Blue Ridge Outdoors’ Leonard Adkins camped beside the Fifteenmile Creek ford, 4.5 miles in, and points to the many streamside spots along Big Run for a second night.

Trail facts

Distance: About 36 miles as a loop (NPS, 2015); forest trail 17.8 to 20 miles depending on source
Route type: Loop
Difficulty: Moderate to difficult on the forest trail; easy on the towpath
Campsites: Backpack camping in the forest by registration; towpath sites at Devils Alley, Stickpile Hill, Sorrel Ridge, Paw Paw Tunnel, Purslane Run, and Town Creek
Water: Many streams on the forest trail; seasonal well pumps on the towpath; treat everything
Permits: Register at Green Ridge Headquarters; no permit for towpath hiker-biker sites
Fires: Allowed in the forest except in drought; fire rings only on the towpath
Trailheads: Lock 58 area near Little Orleans; Lock 67 area off MD 51
Last verified: October 7, 2026

The Lowdown

Twenty-six crossings on Big Run:

One writer counted more than 60 stream crossings on the Green Ridge Hiking Trail, 26 of them on Big Run, and camped by the Fifteenmile Creek ford 4.5 miles in. Five tips for keeping that many crossings safe.

Get the five tips →

Where this comes from

This page draws on the sources below, along with other guides and trip reports. Links go to the original pages.

Before you go: This page is based on published trail guides, trip reports, and reviews, along with official park and agency information where we could find it. It’s meant to help backpackers discover new trails, not to replace current, official information. Conditions, closures, permits, campsites, and water sources change, and some details here may be out of date or wrong. Confirm everything with the managing agency and check current conditions before you head out, and don’t rely on this page alone for safety or navigation. Backcountry travel involves risk.