What number was almost given to the U.S. Route that travels over the Cairo Mississippi Bridge?
Cairo Mississippi River Bridge: The Cairo Mississippi River Bridge is a type of cantilever bridge known as a Steel Truss Through Deck carrying U.S. Route 60 and U.S. Route 62 across the Mississippi River. U.S. Route 60:  In fact, US 66 was almost given the US 60 number.
66