The Sideling Hill Road Cut on Interstate 68 and US 40 in Western Maryland, is a 340 foot deep notch excavated from the ridge of Sideling Hill.  It is notable as an impressive man-made mountain pass, visible from miles away, and is considered to be one of the best rock exposures in Maryland and the entire northeastern United States.  This is the bridge that runs over the highway.

To see images of that notable notch, visit Life on the Bike