 A highlight of the trip is passage along the South Branch Potomac River through "The Trough", an area noted for bald eagle sightings.The PESR runs on the track of the South Branch Valley Railroad, which was established by the state of West Virginia in 1978 to operate a line abandoned by the B&O.Freight service on this line operates on weekdays and occasionally on weekends, so the line is free for excursions on most weekends.