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Mountain biking trails

Black Rock Mill – Pennyfield Lock loop from Twinbrook

Routes

Mountain biking trails

Black Rock Mill – Pennyfield Lock loop from Twinbrook

Hard

2.5

(21)

riders

Black Rock Mill – Pennyfield Lock loop from Twinbrook

09:03

115km

870m

Mountain biking

Hard mountain bike ride. Very good fitness required. Suitable for all skill levels. The starting point of the route is accessible with public transport.

Last updated: April 8, 2026

Tips

Includes a segment in which cycling is not permitted

After 18.5 km for 87 m

Waypoints

Start point

Train Station

Get Directions

13.2 km

Cabin John Stream Valley Park

Nature Reserve

20.4 km

Chesapeake and Ohio Canal

Lake

27.2 km

Widewater

Lake

29.2 km

Start of the Great Falls Foot Trail

Highlight • Trail

The Great Falls of the Potomac is a place with various rapids and small falls in the Potomac. The place marked here may only be entered on foot. Bicycles and dogs 😜 must stay outside.

Translated by Google •

Tip by

40.9 km

Blockhouse Point Conservation Park

Nature Reserve

47.6 km

Muddy Branch Stream Trail

Highlight (Segment) • Trail

A beautiful natural surface trail that gently rolls along the Muddy Branch Stream for nine miles.

Tip by

61.1 km

Seneca Creek State Park is a beautiful place to ride, especially during the fall when the landscape comes alive with color. Film fans might recognize it as a filming location for 'The Blair Witch Project'. Maybe don't visit at night...?

Tip by

62.8 km

Black Rock Mill

Highlight • Historical Site

Just the walls remain of the 1815 Black Rock saw- and gristmill in Seneca Creek State Park. The structure was stabilized and representations of mill machinery were added in 1980.

Tip by

70.7 km

Dry Seneca Creek Stream Crossing

Highlight • River

Crossing Dry Seneca Creek on stepping stones.

Tip by

76.3 km

Riley’s lock

Highlight • Monument

Riley’s Lock is a fun, happening place. Every time I pass by it is bustling with activity. There are two row boat clubs along Seneca creek. There are kayak, jet …

Tip by

81.4 km

Pennyfield Lock

Highlight • Monument

Lock 22, aka Pennyfield Lock, was built between 1829 and 1831, and the name came from the misspelling of the Pennifield family name. It has been restored and offers overnight stays to recreate the rustic feeling from that period.

Tip by

106 km

Viewpoint

108 km

Rock Creek Trail

Highlight (Segment) • Trail

There's a trail following the Rock Creek. The small river runs through the middle of the forest and it's nice to cycle along through the whole year.

Tip by

115 km

End point

Train Station

Way Types & Surfaces

Way Types

82.1 km

16.2 km

6.58 km

4.81 km

4.04 km

531 m

312 m

Surfaces

63.1 km

19.9 km

12.1 km

11.5 km

7.05 km

953 m

Elevation

Nothing selected – click and drag below to see the stats for a specific part of the route.

Highest point (150 m)

Lowest point (20 m)

Weather

Today

Tuesday 23 June

23°C

17°C

57 %

Additional weather tips

Max wind speed: 15.0 km/h

to get more detailed weather forecasts along your route

Comments

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Our route recommendations are based on thousands of hikes, rides, and runs completed by other people on komoot.

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Black Rock Mill – Pennyfield Lock loop from Twinbrook

Start of the Great Falls Foot Trail

Muddy Branch Stream Trail

Seneca Creek State Park

Black Rock Mill

Dry Seneca Creek Stream Crossing

Riley’s lock

Pennyfield Lock

Rock Creek Trail

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