The South Branch of the Potomac River, with its two major tributaries, the North Fork and South Fork, drains all of Pendleton County and parts of Grant, Hardy, Hampshire, and Morgan counties in West Virginia. This amounts to nearly 1,500 square miles, more than 40 percent of the eight-county Eastern Panhandle. Originating just across the state line near Monterey, Virginia, the South Branch traverses about 131 miles before joining with the North Branch near Green Spring to form the Potomac River.

With the exception of two stretches, the South Branch is easily accessible by various roads. An 11-mile section in Grant County upstream of Petersburg, known as the Smoke Hole, is accessed by no public roads; and the six miles of river known as the Trough, situated in Hardy and Hampshire counties between Moorefield and Romney, has only a railroad.

There are no large towns along the North Fork before it unites with the South Branch just upstream from Petersburg, only villages such as Circleville and Seneca Rocks. The South Fork also passes only small villages such as Sugar Grove and Brandywine before joining the South Branch at Moorefield. The South Branch itself meanders through or near sizable towns such as Franklin, Petersburg, Moorefield, and Romney.

The main use of the South Branch watershed is agricultural, but manufacturing, timbering and construction, tourism, and recreation are increasingly important. There has been a vast increase in the last decade in poultry production, primarily broiler chickens raised by growers throughout the watershed and processed mainly at plants at Moorefield. This increase in poultry production and the resulting large amounts of litter and manure have raised concerns about the water quality of the South Branch drainage.

The South Branch has long been noted for its premier smallmouth bass fishing. The smallmouth bass, not native to the South Branch, was first introduced into the C&O Canal basin at Cumberland, Maryland, in the 1850s. The fish escaped from there into the nearby North Branch of the Potomac, later spreading through the watershed. Although other stockings followed, this original stocking numbered about 30 fish. From this we have the tremendous fishery that provides recreation to countless numbers of anglers each year and has given the South Branch a respected name among fishermen in the Mid-Atlantic region. Other commonly sought species are channel catfish, sunfish, and rock bass, in addition to trout (which are stocked during the spring and fall in the upper South Branch).

The Division of Natural Resources has developed several points of access to the South Branch to allow fishermen, as well as pleasure boaters and swimmers, use of the river. These access points permit float trips of various lengths, and at least two canoe rental and shuttle services are available on the river. Due to their inaccessibility by road, the Smoke Hole and Trough sections are probably the most popular floats. Although the Smoke Hole section is floatable for a shorter period of time due to its upstream location and steeper gradient, it is regarded as the most scenic and remote float on the South Branch. A float in the Trough is noteworthy because the floater almost always is ensured of seeing the majestic bald eagle. The Trough was the first known nesting site in West Virginia in modern times for the nation's symbol, and these opportunities should be available for future generations on this wonderful stream of the Eastern Panhandle.