| Montana Secondary Highways | |
|---|---|
  Highway marker for S-236 and S-323 | |
| System information | |
| Maintained by MDT | |
| Formed | 1942 |
| Highway names | |
| Interstates | Interstate n (I-n) |
| US Highways | U.S. Highway n (US n) |
| State | Montana Highway n (MT n) |
| Secondary | Secondary Highway n (S-n) |
| System links | |
The secondary highway system is a lower-level classification of state highway maintained by the Montana Department of Transportation (MDT) in the US state of Montana. Secondary highways first appeared on the state highway map in 1960,[1] even though the secondary system was established in 1942.[2] With very few exceptions, notably MT 287 and the former MT 789, Montana state highways numbered 201 and higher are secondary highways.
The highway markers for Montana's secondary highways are distinctive in that the route number appears in black on a white downward-pointing arrowhead. Early markers were white numbers on black arrowheads with the word Montana in the flat top of the inverted arrowhead and Secondary appearing below the route number on the shields.
- ^ Cite error: The named reference
MDTMAP1960was invoked but never defined (see the help page). - ^ "Federal-Aid Road Log" (PDF). Helena: Montana Highway Department. January 1, 1943. Retrieved May 5, 2017 – via Archive.org.