Near South Run - Mercer Lake Loop Route
Foggy Lake Mercer on a warm, January day.
Near South Run - Mercer Lake Loop Route
North & South Mercer Lake Loop Trails intersection. Keep left to follow South Trail. You'll return on the North Trail.
Near South Run - Mercer Lake Loop Route
Bridge over stream at southern side of lake.
Near South Run - Mercer Lake Loop Route
View of Mercer Lake looking west from top of dam.
Near South Run - Mercer Lake Loop Route
Unpaved section of trail (service road). Trail is in great shape. Easy walking/running.

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Hike Route

South Run - Mercer Lake Loop Route

4.4 (12 Ratings)
A 4.3-mile lollipop loop hike from South Run Recreation Center around Mercer Lake and return.
4.1
mi
Distance
128
ft
Gain
moderate
Difficulty
BirdingFall ColorsFamily FriendlyLakeRiver/Creek

Route Details

Flatter
Steeper
4.13mi
Distance
128ft
Elevation Gain
128ft
Elevation Loss
20%
Max Grade
292ft
High Point
218ft
Low Point
Path Type
Loop
Description
The trailhead is located at the gravel parking area on the south side of the building furthest from the South Run Recreation Center Park entrance at the Fairfax County Parkway. The route utilizes the South Run Stream Valley Trail and the Lake Mercer South Loop Trail to complete the loop around the lake. The trail consists of mostly gentle rolling wooded hills and flats, following a stream bed and encircling Lake Mercer. There are a few steep but short climbs. The trail is mostly paved doubletrack with a few sections being flat and unpaved gravel. The longest climb comes as you approach the dam on the east side of the lake. After crossing the dam, the trail serves as a boundary between townhouses and the woods for a stretch. Most of the trail is shaded with only a few sections open to the sky. The trail is in great shape and makes for a very enjoyable outing.

Route Conditions

Report Conditions
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Contributors
Victor Stephenson