I found this on Wikipedia. I know that Wikipedia is not reliable, and this portion is not sourced, but is it true or not?
QuoteAbout three miles (5 km) later at East Leavenworth, Missouri, Route 45 intersects its spur which goes northwest to Leavenworth. The spur, which is signed as "Route 45" and also known as the "Leavenworth cutoff", was built as a shortcut from Leavenworth, Kansas to Kansas City during the construction of the Centennial Bridge (Leavenworth, Kansas). Even though it is in Missouri it was maintained by the city of Leavenworth until the tolls were removed from the Centennial Bridge in May 1977. This is now maintained by MODOT.
It doesn't make sense to me that a city in Kansas would maintain a road that is well within Missouri but stranger things have happened. I call bullshit but who knows.