This is a very short hike, but it offers several rock climbing options just off trail that can keep you busy for more than a couple hours. In addition, because the trail to Mount Marshall's summit is the Appalachian Trail, you can pretty much keep going as long as you want on the trail to explore other parts of the northern Shenandoah Mountains. Mount Marshall is made up of two summits. South Marshall and North Marshall. This route only climbs North Marshall, from the ridge between the two mountains.
Up the Appalachian Trail on the incline to Mount Marshall
From Washington DC, take 66 West to exit 13. Go west and follow signs for Shenandoah National Park. Drive down Skyline Drive past milepost 15. There is a parking lot at milepost 15.9 on the left if you are going South, so if you see milepost 16, you probably just missed the parking lot.
The Appalachian Trail is right behind the parking lot. You take the trail to the north and hike up the hilly trail, with a couple switchbacks. Perhaps the most prominent feature along this trail is what I call "The Fist"
This rock takes about 3-4 minutes to climb and it just one of the several cliffs you can reach on the trip. Several more are located to the north of the fist and require some bushwhacking to reach. One is about 50-100 feet higher and also has nice views.
To reach the summit you will pass an overlook along the AT. Here are more cliffs which you venture out onto.
Mount Marshall Cliffs
After passing this overlook, you head back into the woods. The trail rises slightly, then dips slightly, then rises again. The summit is evident on the left of the trail, because the trail does not go any higher. The summit is a bunch of boulders in a small clearing. A USGS marker identifies this as the highest point.
Without venturing onto boulders and cliffs, the total hike round trip is only about 1.5 miles with 300' of elevation gain.