Why is WY 789 numbered as such?
It was part of a longer multi-state SR 789. In the 1950s and 1960s it went from the Mexican border in Arizona to the Canadian border in Montana. The only state that didn’t just multiplex 789 with other state/U.S. routes was Wyoming,and when Arizona, New Mexico, Colorado and Montana got rid of their 789s in the late 1970s, Wyoming was left with a weirdly numbered route, which remains to this day. More information: WY: http://www.rockymountainroads.com/wyoming/us-789.html CO: http://www.mesalek.com/colo/r400-789.html#789 Dec 4, 2004 8.5 Q: Why is FL A1A numbered (and lettered) as such? A: Florida uses the grid system for its state highways, which puts 1 on the Atlantic coast. However, when U.S. Highways were created, US 1 was run into Florida parallel to and very close to FL 1. To avoid confusion, FL 1 was renumbered FL A1A (1A was already in use). (See http://en.wikipedia.org/wiki/Florida_State_Road_A1A ) And yes, Alternate A1As have existed. There have also been a FL A19A and a FL G1A.
