Mile 99.80 - The Conococheague river runs right beside the Cushwa basin and empties into the Potomac here. This and the aqueduct at Antietam both have 3 arches. The wall you see here collapsed in 1920 after being hit by a canal boat. The wall had been progressively weakened and the boat captain was not held to blame. The barge lay at the foot of the aqueduct for another 16 years until washed away by the 1936 flood.
I love this sign!