Its not a hike or a bike ride, but worth seeing if you are in the area. Just over the Mason-Dixon Line, on Route 272 in Maryland, is Gilpin’s Falls Bridge. Maryland has few covered bridges surviving, and Gilpin’s is one of the older ones, celebrating 155 years. After years of neglect it underwent a thorough restoration in 2010 and its in great shape.
Access to the bridge is via a pulloff on the northbound side of Route 272. The falls in its name aren’t reachable from the bridge, as there’s a dam on the creek and fencing preventing anyone from getting near them. That said its a great looking bridge, and its well worth a few minutes to visit and photograph.