- ... that a 156-foot (48 m) tunnel for the Lower Manhattan Expressway was built in New York City in the 1960s, but was never used?
- ... that Wyoming Highway 89 is so numbered from a failed proposal for U.S. Route 89 to stay in that state rather than enter Idaho?
- ... that M-67, a state highway in the Upper Peninsula of Michigan, has remained essentially unchanged but the highways connecting to it have changed three times since 1919?
- ... the highest road in the Utah state route system is Utah State Route 150 over Bald Mountain Pass [elevation 10,715 feet (3,266 m)]?
- ... that WIS 35 is the longest highway in Wisconsin?