TransAction 2040, Northern Virginia's long-range transportation plan, calls for a new Potomac River "Crossing," linking Prince William or Stafford counties in Virginia with Charles County in Maryland.  The plan estimates this project, still highly conceptual, would cost $1.23 billion. The length of the proposed corridor would be 15-20 miles, stretching between I-95 in Virginia and U.S. 301 in Maryland.