Steepest state routes

[Arkansastravelguy]

On AR 155 at Mount Nebo. Is there a steeper state route? Besides Hawaii.


iPhone

[hotdogPi]

Are there any state routes that are roller coasters?

[oscar]

The only steeper route in Hawaii is not a state route.

Part of CA 108, east of Sonora Pass, is posted at a 26% grade.  It did not seriously strain my four-cylinder rental car when I traveled it westbound, so the grade must be either overstated or very short.

[Arkansastravelguy]

This grade is for over 2 miles


iPhone

[Revive 755]

While not as steep as the California grade mentioned, MO 376 in the Branson area has a grade singed for 19%:

Streetview of sign

[hbelkins]

What is the evacuation marker in the background for?

[sdmichael]

The only steeper route in Hawaii is not a state route.

Part of CA 108, east of Sonora Pass, is posted at a 26% grade.  It did not seriously strain my four-cylinder rental car when I traveled it westbound, so the grade must be either overstated or very short.

The 26% section is not long, but noticeable. Overall, Sonora Pass has rather steep grades for extended periods, mostly on the eastern side. To my knowledge, it is the steepest grade posted on ANY State Highway in California.

[US71]

What is the evacuation marker in the background for?

Arkansas Nuclear One Emergency Evacuation, most likely