Montana Secondary Highway 421, US-212 to MT-78


AMP: 18

Location: S-421 and US-212, Carbon Cty

No reassurance shield as 421 begins.

AMP: 8

Location: S-421 at the Carbon County Line, Stillwater Cty

Reassurance shield about halfway down the route as we enter Stillwater County.

AMP: 0

Location: S-421 and MT-78, Carbon Cty

A few miles later, we’ll approach Highway 78.

AMP: 0

Location: S-421 and MT-78, Stillwater Cty

Turn right for 78 west into Columbus and left for 78 east towards Red Lodge.

 S to S-420, N to S-306

 E to US-310, W to MT-78