Prettyboy Dam Loop (Gunpowder Falls State Park) Hiking Guide
This loop follows the Big Gunpowder Falls upstream from Masemore Road to the foot of Prettyboy Dam, then climbs away from the river on the Highland Trail for a quieter return. The riverside half is rocky and slow, with boulders to climb over. Parking is free and the setting is wooded the whole way.
The Route
Hiking Project's Prettyboy Dam Loop is 4.3 miles with 379 feet of gain. From the south side of the old Masemore Road bridge, head west on the white-blazed Gunpowder South Trail. The path narrows and soon reaches big rocks you scramble over, then returns to the water's edge. The author's advice where the path is unclear: stay near the river. Near the dam the air cools noticeably. Head back to a small stream crossing, turn south onto the Highland Trail, climb through the woods, and rejoin the white trail back to Masemore Road.
Parking and Access
From I-83, take exit 27, turn left on Mount Carmel Road and right on Masemore Road. Parking by the bridge is limited to about ten cars, according to the route's author, and there are no restrooms. Like the rest of the Hereford Area, it is open sunrise to sunset, and the park charges nothing to park here.
River and Woods
The park describes the Hereford Area as 3,620 acres of protected wildlands with more than 20 miles of trail. Below Prettyboy Reservoir the river is a special trout management area, so expect fly anglers in the water. The nearby Masemore Hemlock Ravines natural area has steep, rocky slopes of hemlock, chestnut oak and mountain laurel that feel more like the mountains than northern Baltimore County.
Fall Hunting Days
Two zones in the Hereford Area are open to archery deer hunting with a free permit. DNR sets the hunting days for each zone every season and posts them on the Hereford Area page, so check it before a fall weekday hike. Sundays are the quietest choice in the fall; on other days wear orange and stay on the trail.
Footing and Dogs
Blazes are present but intersection signs are few, so download a map before you lose signal. Poles help on the boulders, and bug spray earns its place in summer. Dogs may come on a leash; the park allows them throughout its undeveloped areas as long as owners clean up after them. Pack out all trash.
Hiking tips for Prettyboy Dam Loop (Gunpowder Falls State Park)
- Get to Masemore Road early; the small lot fills on nice weekends.
- Keep to the riverbank when the white trail gets faint among the rocks.
- Bring trekking poles for the boulder sections.
- Hike on a Sunday during fall archery season for the fewest hunters.
- Pack water and plan for no restroom at the trailhead.
Nearby trails to explore
- Cascade Falls Trail (Patapsco Valley State Park)
- King and Queen Seat Loop (Rocks State Park)
- Kilgore Falls Trail
Hike this trail with TrailMates
The Prettyboy loop is close to Baltimore but feels remote, which makes company welcome. Post a hike on TrailMates, agree in the event's group chat who drives so the small Masemore lot is not overloaded, and meet at the old bridge. Download TrailMates on the App Store or Google Play.