Wind River Canyon Scenic Byway

Shoshoni to Thermopolis

Central Wyoming · Wyoming · United States

Key measurements

Distance

32.4 miles

Elevation gain

905 ft

Elevation loss

1,415 ft

High point

4,891 ft

Low point

4,328 ft

Net change

-510 ft (4,838 ft to 4,328 ft)

Surface

Paved

Route type

point-to-point

Route Overview

The Wind River Canyon Scenic Byway follows US-20/WY-789 for 32.4 miles from Shoshoni to Thermopolis, crossing the high desert around Boysen Reservoir before plunging through Wind River Canyon into the Bighorn Basin. Beginning in the open sagebrush plains of Shoshoni, the route skirts the edge of Boysen Reservoir before cutting directly into the Owl Creek Mountains via Wind River Canyon. As the river carves its way north, the road follows its floor between sheer, multi-colored canyon walls that expose striking geological strata millions of years old. The canyon releases into the southern end of the Bighorn Basin, concluding in the thermal spring town of Thermopolis.

Key Segments & Geographic Transitions

High Desert Basin & Lake Approach — Miles 0.0–21.9

Leaving Shoshoni, the route heads north across open, windswept high-desert terrain. The road works past the margins of Boysen Reservoir, cresting its high point of nearly 4,890 feet around Mile 9. The landscape here is broad and arid, characterized by expansive views, distant mountain profiles, and long sweeping stretches of open asphalt. As the segment progresses, the flat terrain begins to close in, funneling toward the northern mouth of the lake and the impending mountain barrier ahead.

Wind River Canyon Gorge — Miles 21.9–32.4

At the head of the canyon, US-20/WY-789 merges with the river and plunges into the Owl Creek Mountains. The character of the ride shifts instantly from wide-open basin to a tight, winding corridor flanked by towering rock cliffs that rise up to 2,500 feet above the riverbed. The route traces the contours of the Wind River, passing through three blasted bedrock tunnels and descending steadily to its low point of 4,328 feet at the canyon’s northern end. The segment exits near "Wedding of the Waters"—where the Wind River officially becomes the Bighorn River—before rolling straight into Thermopolis.

Seasonal & Environmental Context

Wind River Canyon is elevated desert terrain subject to rapid environmental shifts. Summer brings high daytime heat, though temperatures inside the canyon gorge can be noticeably cooler than the open plains due to shadow and river proximity. Crosswinds can be intense along the open shoreline of Boysen Reservoir. Spring and autumn bring significant freeze-thaw cycles, which increase the likelihood of rockfall on the pavement within the canyon walls.

Logistics & Services

Given the short 32-mile distance, fuel strategy is simple, but options are concentrated entirely at the endpoints. Complete services, fuel, and supplies are available in Shoshoni and Thermopolis, but there are no commercial services or gas stations along the highway inside the canyon or around Boysen Reservoir. Cellular coverage is generally reliable in the basins but frequently drops out inside the deep stone walls of the canyon.

Important Considerations

Rockfall is a persistent, real risk throughout the canyon segment, particularly after heavy rain or during seasonal temperature swings. Bighorn sheep frequently gather along the narrow gravel shoulders and can step directly into the roadway. Additionally, entering the three unlit canyon tunnels requires immediate adjustment to rapid light changes when traveling from bright sunshine into shadowed rock cuts.