I'm not sure if it is an official route, but there is a well-signed truck route for MT42 in Glasgow, MT.
The route begins/ends at intersection of 1st Ave North and 6th St North (the waypoint where MT42 meets US2). From there it runs along 1st Ave North to 4th St North where it turns south and crossed the railroad tracks before meeting up with MT42 at the existing waypoint labeled 4thSt. The entire route probably isn't much longer than a quarter mile, but is appears to have been signed in
GMSV for quite time time.
Here is a newer image at the intersection where the route turns.
The route is signed well enough to easily follow. I'm guessing it exists due to the height restriction of 12'3" at the railroad underpass on MT42.
Should this be added to the HB?
