Benjamin Henry Latrobe II

of Philadelphia, Pennsylvania
http://en.wikipedia.org/wiki/Benjamin_Henry_Latrobe,_II

B&O - Harper Ferry Bridge (Jefferson County, West Virginia)
Designer, 1836
Lost Through truss bridge over Potomac River on Former B&O
Destroyed by disaster

CSX - Thomas Viaduct (Howard County, Maryland)
Designer, 1835
Eight-span stone arch bridge over Patapsco River on the B&O Railroad between Relay and Elkridge
Open to traffic

ST - Hoosac Tunnel (Berkshire County, Massachusetts)
Built 1854
Tunnel under Hoosac Mountains on Pan Am Railways
Open with daily traffic