In my ongoing quest to follow the fall foliage, this week, we’ll travel to Shenandoah National Park in the Blue Ridge Mountains. October in Virginia would not be complete without a trip to scenic Skyline Drive! 🍃🚗🍁
Sharon Lyon
Editor, GeoLifestyle
Skyline Drive/Shenandoah National Park, Virginia
Overlooking the Shenandoah Valley from Skyline Drive, VA.
Skyline Drive is a scenic roadway in Virginia that runs for 105 miles through Shenandoah National Park in the Blue Ridge Mountains. The mountains are named for the distinctive mists that give them a blue tinge. Volatile organic compounds from evergreens scatter blue light, giving the mountains their hazy, blue appearance.
Area geology: The park lies within the Blue Ridge Physiographic Province of the Appalachian Mountains.
Shenandoah’s geology reflects a deep history of continental collisions, rifting, ocean formation, mountain building, and erosion.
During the Grenville continental collision that assembled the supercontinent of Rodinia, granitic rocks formed the ancient mountain core. The vestiges of these rocks are seen today as granodiorites and the granite-gneisses of the Pedlar Formation and the Old Rag granite.
As Rodinia rifted apart in the late Precambrian, 570 million years ago, volcanism in the form of basaltic lava flows and pillow basalts formed the Catoctin Formation. These basalts were later metamorphosed to form greenstones.
The early Iapetus Ocean formed in the shallow marine rift basin, and sandstone, quartzite, conglomerate, and shale were deposited.
During multiple tectonic events (the Taconic, Acadian, and Alleghanian orogenies), 450–300 million years ago, the rocks were uplifted, faulted, and thrust westward. It is estimated that the ancient Appalachian Mountains were once as high as today’s Himalayas.
The overlying rocks have been largely eroded, and today’s rounded peaks reflect this long-term erosion of the ancient mountains.
Topography: The crest of the Blue Ridge Mountains is shaped by resistant quartzites, gneisses, and greenstones. Waterfalls are found along steep slopes and V-shaped stream valleys.
There are 75 scenic overlooks in Shenandoah National Park, enabling you to view the Shenandoah Valley to the west and the Piedmont Physiographic Province to the east.
Trip tips:
Enter Skyline Drive at one of four entrances (Front Royal, Thornton Gap, Swift Run Gap, or Rockfish Gap). You must pay a fee or use your National Parks Pass.
Skyline Drive and Shenandoah National Park are very popular in leaf season, so arrive early. Get a map at the entrance station or at one of the visitor centers. Mileposts are numbered north to south.
Obey the 35-mile-per-hour speed limit and watch out for wildlife. The road is windy and can be slippery when wet.
Bears: A population of black bears lives in the park. They are especially active in early morning and at dusk. Give them plenty of room. Do not feed the bears!
Hiking: There are more than 500 miles of hiking trails, including 101 miles of the Appalachian Trail in the park. Most trailheads are located along Skyline Drive.
Trails vary in difficulty from short walks to challenging hikes.
My favorite day hike is the moderate, 2.4-mile trail to Compton Peak to view the columnar basalt of the Catoctin Formation. The metamorphosed basalt (now greenstone) displays its interlocking polygonal columns.
Park at the Compton Gap Parking Area at mile 10.4 on Skyline Drive. Be aware that the parking area can fill up quickly. Part of the trail is rough and rocky, but the outcrop is worth the hike.
Pit stop: Skyland and Big Meadows (Byrd) Visitor Centers have nice picnic areas. Food is available at the visitor centers, but I recommend packing a picnic lunch because the wait at the restaurants can be very long.
The end of the road? Skyline Drive ends at the southern end of the park at Afton Mountain, where it connects to the Blue Ridge Parkway.
But you can keep on going! The Blue Ridge Parkway is a 469-mile road that runs through the Blue Ridge Mountains of Virginia and into North Carolina, eventually leading to Great Smoky Mountains National Park.
Note that currently, Skyline Drive is closed due to the government shutdown. We hope to see it reopen soon!
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Years ago, one of my first backpacking experiences was to hike and camp on Old Rag Mountain. The trip was a rite of passage for Virginia college students who liked the outdoors. Today, I recommend the experience to those with better knees than mine.
Area geology:
The most popular destination within Shenandoah National Park, Old Rag Mountain is one of the few places in the park where hikers can walk directly on billion-year-old basement rocks. The peak is famous for its rocky summit with 360-degree views.
The mountain is composed of Grenville-aged (1.0–1.2 billion-year-old) Old Rag granite. In places, the granite has been metamorphosed into granitic gneiss. The rocks are some of the oldest exposed rocks in Virginia.
Old Rag’s distinctive peak, rising 3,284 feet, is an example of an exfoliation dome, formed by unloading and expansion as the overlying rock units were eroded off.
Trip tips:
Hiking to the summit is physically demanding. The trail is between eight and 10 miles long, depending on where you park. You climb up and down about 4,800 vertical feet and scramble over large boulders.
Hikers must pay an entrance fee at the Old Rag Ranger Station.
From 1 March to 30 November, visitors to Old Rag must also obtain an Old Rag day-use ticket in advance. A total of 800 tickets per day are issued.
Camping: Camping is prohibited above 2,800 feet, and legal overnight camping sites are very limited on Old Rag.
Backpacking: Backpackers must purchase a permit from Recreation.gov.
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