Mirror Lake Scenic Byway

Kamas to Evanston

Northern Utah / Southwestern Wyoming · Utah · United States

Key measurements

Distance

77.8 miles

Elevation gain

4,873 ft

Elevation loss

4,517 ft

High point

10,722 ft

Low point

6,485 ft

Net change

356 ft (6,485 ft to 6,841 ft)

Surface

Paved

Route type

point-to-point

Route Overview

This 77.8-mile mountain crossing traverses the High Uinta Mountains along the Mirror Lake Highway (UT-150 and WY-150), linking the agricultural Kamas Valley in Utah to the high-desert country of Evanston, Wyoming. Beginning at 6,485 feet in Kamas, the highway follows the Upper Provo River upward into dense pine and aspen forests, climbing steeply to clear the alpine crest at Bald Mountain Pass (10,721.7 feet) near mile 29.1. From the pass, the route descends along the upper reaches of the Bear River, crossing the state line and transitioning from subalpine forest to open sagebrush rangeland before dropping into Evanston.

Key Segments & Geographic Transitions

High Uintas Alpine Ascent and Bald Mountain Pass — Miles 0.0–54.5

Starting at the base of the Uinta Range in Kamas, UT-150 enters the Uinta-Wasatch-Cache National Forest and climbs alongside the Provo River. The road winds through carved canyons and granite basins, gaining over 4,200 feet of elevation. Curves tighten as the road climbs past timberline toward Bald Mountain Pass, where the route reaches its peak elevation of 10,721.7 feet. Past the high point, the highway negotiates a series of descents through alpine lake basins into the Bear River drainage, maintaining high-altitude forest cover up to the Wyoming border at mile 54.5.

Bear River Valley Descent to Evanston — Miles 54.8–77.5

Crossing into Wyoming, the road transitions to WY-150. The tight mountain geometry relaxes into sweeping, open curves as the pine forests give way to high-sagebrush valleys and wide floodplain pastures. Following the Bear River north, the highway steadily drops roughly 4,200 feet over 22.6 miles, offering wide vistas of the Northern Uinta foothills before ending in the high plains surrounding Evanston.

Seasonal & Environmental Context

The corridor over Bald Mountain Pass is strictly seasonal, generally closing under heavy snowpack by late autumn (typically November) and reopening in late May or early June depending on winter accumulation. Due to the high peak elevation, temperatures at the pass can be 20 to 30 degrees cooler than in Kamas or Evanston. Afternoon rain, hail, and sudden thermal drops are common summer occurrences across the high spine of the range.

Logistics & Services

Fuel and services are available at both ends of the route in Kamas and Evanston, but the 50-mile wilderness stretch between them offers no commercial gas or retail services. Cell service is unreliable or nonexistent through much of the national forest segment. Recreators stopping at designated pullouts or trailheads along the Utah portion of the corridor require a National Forest recreation pass.

Important Considerations

Riding at elevations exceeding 10,000 feet reduces engine power on naturally aspirated motorcycles and accelerates rider dehydration and fatigue. Winter weather damage creates freeze-thaw asphalt cracking, frost heaves, and loose gravel accumulation in tight mountain corners, particularly after rainstorms. Wildlife is abundant throughout the corridor; deer, elk, and moose frequently cross the roadway in the forested sections along the river drainages.