IRON BRIDGE (National Road Brownsville PA)
Once upon a time this was a beautiful and graceful structure--the first cast-iron bridge in the US. It went up in 1838 and remains in service, heavily modified. Iron is visible on the left forming the repeating letters M and W right under the concrete deck.
Rusting steel beams and reinforced concrete piers carry much of the weight today, hiding most of the original beauty.