The inset map for Hannibal, from the official 1950 Missouri highway map. There's no longer an Alternate US 36, and City Route US 36 is now Business US 36. What was then Route AA is now Missouri 79. Missouri 56 is now Missouri 168. Other alignments have changed, and the old bridge across the river was demolished in 2001 after being replaced by the new Mark Twain Memorial Bridge to the north, carrying Interstate 72 across the Mississippi River.