Western Colorado’s Steepest Roads: Grades Up To 12% Challenge Drivers

If you have ever driven to the top of the Pike's Peak Highway, you may remember a portion of the road with a running slope of over 12%. If you have driven up the Mount Blue Sky Scenic Byway, you've traveled a slope of 8.4%. Have you ever wondered which roads have the steepest grades in Western Colorado?

Read More: Colorado's Amazing Sky High Mountain Passes Ranked By Elevation

The steepest highways in Western Colorado are just as challenging for drivers as any on the Front Range. Keep reading to learn where three of the steepest grades are on this side of the Rockies.

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The Grand Mesa Scenic Byway (State Highway 65)

Western Colorado's Grand Mesa Scenic Byway has one of the steepest grades on any paved road on the Western Slope. A portion of the route between Cedaredge, Colorado, and the top of the World's largest flattop mountain has a grade between 10-12%

Slumgullion Pass (State Highway 149)

Southwestern Colorado's State Highway 149 is home to the Slumgullion Pass. A portion of this pass reaches a grade of 9.4% before climbing to an elevation of 11,530 feet. Drivers who brave the pass will find some of the best views of the San Juan Mountains from the overlooks, including a great view of Lake San Christobal overlook along the way.

Read More: One of the Steepest Highways in America is Right Here in Colorado |

Red Mountain Pass (U.S. Highway 550)

For anyone who has driven over the Million Dollar Highway, you may remember one of the steepest sections is Red Mountain Pass as you cross over the San Juan County line. The pass is known for steep grades, sharp turns, a lack of guardrails, and grades between 8 and 9%.