Originally Posted by RiponredTJ
Is that an ice bridge in that last picture?
We have an ice breaking bridge structure upstream from the Champlain and Jacques Cartier bridges to help prevent ice damage and blockage.
The bridges have those concrete wedges at water line but floods overwhelm them. Lee was on his way to Harrisburg when he was interrupted at Gettysburg. Lee was after the railway lines that met there. It was the many bridges that together built up an ice dam at the real dam you see in the B&W photo as well as at RR crossings.