Apparently, the bridges in one of the busiest corridors in the US rails system are fast turning to junk:
The massive rail bridges over 52d Street in West Philadelphia are a portrait of neglect.
Trees grow from their ramparts, water weeps through their stone walls, holes are visible in the rusting deck, the piers are cracked, beams are corroding. Trash gathers at the base of the columns.[…]
Amtrak inspectors rate many of its structural elements “poor.” Some components are even worse, marked “serious,” just one grade above “failed.”