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South Run - Mercer Lake Loop Route

Intermediate

Trail

4.3 mile 6.9 kilometer loop
99% Runnable
Intermediate

Elevation

Ascent: 165' 50 m
Descent: -165' -50 m
High: 287' 88 m
Low: 217' 66 m

Grade

Avg Grade: 1% (1°)
Max Grade: 7% (4°)

Dogs

Leashed
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Map Key

Trail shared by Victor Stephenson

A 4.3-mile lollipop loop run from South Run Recreation Center around Mercer Lake and return.

Victor Stephenson

Features Birding · Fall Colors · Lake · River/Creek

Overview

This route provides a nice 4.3-mile lollipop loop route around Mercer Lake. The way is mostly a paved doubletrack path starting at South Run Recreation Center.

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.

Flora & Fauna

Mostly deciduous forest. Lots of squirrels, birds, and small mammals. Occasional deer are also present.

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Check-Ins

Feb 17, 2020
Matthew Deyo
4.1mi
Nov 9, 2017
Rendel Sogueco
Feb 26, 2017
Susana GB
Feb 11, 2017
Keith Smoly
4.3mi
Feb 5, 2017
Keith Smoly
4.6mi

Trail Ratings

  4.3 from 10 votes

#2042

Overall
  4.3 from 10 votes
5 Star
50%
4 Star
30%
3 Star
20%
2 Star
0%
1 Star
0%
Run Rankings

#56

in Virginia

#2,042

Overall
185 Views Last Month
4,375 Since Sep 20, 2016
Intermediate

30%
70%
0%
0%

Photos

Foggy Lake Mercer on a warm, January day.
Jan 4, 2020 near Burke, VA
South Run Stream Valley Trail: gravel doubletrack ends and paved doubletrack begins.
Oct 12, 2016 near Newington, VA
Trail Intersection: South Run Stream Valley Trail and Lake Mercer (South) Trail at north side of Lake Mercer Dam.
Oct 12, 2016 near Newington, VA
South Run Stream Valley Trail on left. Lake Mercer (South) Trail on right crossing Lake Mercer Dam.
Oct 12, 2016 near Newington, VA
Unpaved section of trail (service road). Trail is in great shape. Easy walking/running.
Sep 20, 2016 near Burke, VA
North & South Mercer Lake Loop Trails intersection. Keep left to follow South Trail. You'll return on the North Trail.
Sep 20, 2016 near Burke, VA

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