Casselman River Bridge sits parallel to Route 40 which sits parallel to Interstate 68 just east of Grantsville in western Maryland. The bridge was built in 1813 and by the crest in the road at the center of the bridge you could never drive a car over it today. 354 feet long, 30 feet high with a 48 foot span, it was strengthened in 1911 but closed in 1933. Traffic was moved to a big green steel bridge on Route 40. The bridge was designated a Registered National historic Landmark in 1963.