2.9
(13)
94
hikers
Lake Mercer loop
01:43
6.63km
40m
Hiking
The Lake Mercer loop is a fantastic option for a relaxed outing, offering continuous lake views and a pleasant mix of shaded wooded paths and open sections. This easy 4.1-mile (6.6 km) loop, with just 134 feet (41 metres) of elevation gain, takes about 1 hour and 43 minutes to complete, making it ideal for a quick nature fix. You'll traverse both paved and unpaved gravel paths, enjoying gentle rolling hills and the occasional short, steep climb, especially near the scenic Lake Mercer Dam. Keep an eye out for local wildlife, including deer and various bird species, as you circle the lake.
Parking is conveniently available at South Run District Park and the South Run RECenter, making access simple. The trail is dog-friendly, so your canine companion can join the adventure. While generally easy, some parts of the Lake Mercer walking routes can get muddy after rain, so wear appropriate footwear. This trail is perfect for a morning or afternoon stroll, offering a refreshing escape without requiring a full day's commitment.
Beyond its scenic beauty, the Lake Mercer loop is notable for its accessibility and family-friendly nature, with benches along the way for rest stops. It also connects to other local trails like the South Run Stream Valley Trail and the Burke Lake Loop, providing options for longer excursions if you're feeling ambitious. This makes it a versatile choice for various activity levels and a great way to explore the natural features of Fairfax County.
Last updated: June 9, 2026
Waypoints
Start point
Parking
Get Directions
3.57 km
Lake Mercer
Highlight • Lake
Tip by
6.63 km
End point
Parking
Way Types & Surfaces
Way Types
6.44 km
153 m
Surfaces
4.65 km
1.11 km
537 m
280 m
< 100 m
Sign up to see more specific route details
Sign up for free
Elevation
Sign up to see more specific route details
Sign up for free
Weather
Powered by Foreca
Wednesday 1 July
36°C
23°C
-- %
Additional weather tips
Max wind speed: -- km/h
to get more detailed weather forecasts along your route
This route was planned by komoot.
Frequently Asked Questions
What is the terrain like on the Lake Mercer loop?
The trail features a diverse terrain, primarily consisting of paved sections, but also includes gravel paths. While mostly wooded, you'll encounter gentle inclines and declines, with a few short, steeper climbs. Some areas may have rocky gravel surfaces, and the path is generally wide.
How long does it typically take to complete the loop?
Most hikers can complete the Lake Mercer loop in about 2 to 2.5 hours at a leisurely pace. The total distance is approximately 6.6 kilometers (4.1 miles).
Is the Lake Mercer loop suitable for beginners or families with children?
Yes, the Lake Mercer loop is generally considered easy and is suitable for beginners and families. It's a multi-use trail popular for leisurely strolls, jogging, and biking, making it accessible for various activity levels.
Where can I park and access the trailhead for the Lake Mercer loop?
You can easily access the Lake Mercer loop from South Run District Park or directly within Lake Mercer Park. South Run District Park and the adjacent South Run RECenter offer convenient parking and amenities like restrooms, making it a popular starting point.
Is the trail dog-friendly?
Yes, the Lake Mercer loop is dog-friendly. Please ensure your dog remains on a leash and that you clean up after them to maintain the trail's cleanliness for all users.
What can I see along the route?
The trail offers continuous views of Lake Mercer, especially from the scenic walkway over the Lake Mercer Dam, which has benches for resting. You'll also enjoy largely shaded paths through deciduous trees and opportunities for wildlife observation, including various birds, deer, and even beavers.
What is the best time of year to hike the Lake Mercer loop?
The Lake Mercer loop is enjoyable year-round. However, spring and fall offer particularly pleasant conditions with comfortable temperatures and beautiful foliage. The trail is largely shaded, making it a good option even on warmer days.
Are there any permits or entrance fees required to access Lake Mercer Park or the trail?
No, there are no permits or entrance fees required to access Lake Mercer Park or to hike the Lake Mercer loop trail. It is free and open to the public.
Does the trail intersect other well-known paths?
Yes, the route also passes through sections of the Wagon Trail Lane and the Grass Trail. It also connects to the larger South Run Stream Valley Trail and can link to the Burke Lake Trail at its northern end, providing options for longer excursions.
Are there any specific sections of the trail that are more challenging?
While generally easy, some sections on the south side of Lake Mercer have been noted to have steeper inclines. These are short but can add a bit more challenge compared to the mostly gentle, rolling hills.
What kind of wildlife can I expect to see?
The Lake Mercer loop is excellent for wildlife observation. You might spot various birds, squirrels, deer, foxes, beavers, and turtles. Birdwatchers can look out for herons, eagles, and hawks.
Comments
Want to know more?
Sign up for a free komoot account to join the conversation.
Sign up for free