According to the latest information available, the Old Wharf Road boat ramp located in King George County, Virginia is a concrete boat ramp that provides access to the Potomac River. The ramp is reported to be 20 feet wide and is open to the public year-round.

The Potomac River is a major waterway that stretches over 400 miles, flowing from West Virginia through Maryland and Virginia, and into the Chesapeake Bay. The river is home to a variety of fish species, including bass, catfish, and shad, making it a popular destination for recreational fishing and boating.

As for what types of watercraft are permitted on the Potomac River, it varies based on the regulations of each state and local jurisdiction. In Virginia, all boats, including motorized and non-motorized vessels, are allowed on the river as long as they comply with state and local laws and regulations.

In summary, the Old Wharf Road boat ramp in King George County, Virginia is a concrete boat ramp that provides access to the Potomac River. The ramp is 20 feet wide and is open to the public year-round, allowing all types of boats to be launched into the river.