| According to the Maryland Historical Trust, the Thomas Viaduct, which spans the Patapsco River between Relay and Elkridge, MD, was constructed between 1833 and 1835. It allowed Balitmore and Washington, D.C., to be connected by rail. The viaduct is a multi-span masonry bridge, and was the first of its type to be built on a curving alignment. The largest bridge in the nation in its day, it was named for Philip E. Thomas, first president of the B&O Railroad. It is still in use today--the CSX double-track Capital Subdivision crosses over the viaduct--and MARC Camden Line commuter trains travel over it Monday through Friday. The Thomas viaduct is the world's oldest multiple stone arched railroad bridge. |