The Governor Harry W. Nice Memorial/Senator Thomas "Mac" Middleton Bridge, also known as the Potomac River Bridge, is a 1.7-mile (2.7 km), two-lane continuous truss bridge that spans the Potomac River between Newburg in Charles County, Maryland and Dahlgren in King George County, Virginia, United States. It is one of eight toll facilities operated by the Maryland Transportation Authority, and is one of two toll bridges over the Potomac River. The other, the privately owned Oldtown Low Water Toll Bridge, connects Maryland and West Virginia, far upstream.