Nestled along the picturesque North Fork South Branch Potomac River, near the town of Petersburg, West Virginia, is the unique Triangle Rock. As its name aptly suggests, this geological wonder boasts a rock formation that, in a fascinating twist of nature, mirrors the shape of a triangle.
North Fork Mountain, the imposing backdrop for this formation, forms a part of the renowned Wills Mountain Anticline system. This ridge system spans several states, beginning in Pennsylvania and meandering through Maryland, and West Virginia, and reaching into the heart of Virginia. ts striking silhouette emerges from the southern landscape of the North Fork gap, a renowned water gap located near Cabins. This mountain further breaks down into intriguingly named ridges like the Devil’s Backbone, Brushy Mountain, and Monterey Mountain towards its southern terminus.
What makes North Fork Mountain spectacular is its cap of Tuscarora quartzite or sandstone. This resilient layer of Silurian rock stands up against erosion, resulting in west-facing cliffs and several sizable outcrops. The verdant forests surrounding Triangle Rock are a lush mix of sugar maple, beech, and yellow birch hardwoods, punctuated by stretches of towering red pines. The cliffs of North Fork Mountain, with their bare sandstone edges, give rise to unique ecological niches, including the delicate silvery nailwort and the pristine white alumroot. Adding to this botanical display are the chestnut oak and the Table Mountain pine, often sighted just beyond the cliff edges.