Thermopolis to Baker City: Route Guide

Leaving Thermopolis, WY (43.6461° N, 108.2120° W), the Bighorn River's canyon walls narrow your view, then the road climbs toward the Absaroka Range. This route to Baker City, OR (44.7753° N, 117.8341° W) spans 514 miles via US-20 and I-84, crossing the Continental Divide at 7,900 feet near Togwotee Pass (not that you'll go that far north, but the Divide crossing is at South Pass, 7,416 ft, on US-287).

Driving time is 8–9 hours without stops, but plan for 2 days to absorb the landscapes. The route passes through Wyoming's Wind River Canyon, the Bighorn Basin's sagebrush flats, and Oregon's Blue Mountains, each with distinct geological stories.

Wind River Canyon (mile 10-20) showcases 2.9-billion-year-old granite and limestone cliffs – a geological cross-section. Nearby, Hot Springs State Park in Thermopolis offers free mineral pools, and the Wyoming Dinosaur Center has a dig site.

The route passes the Oregon Trail corridor; Independence Rock (mile 130) has pioneer names carved in the granite. Baker City's downtown has the Oregon Trail Interpretive Center (5 miles east) and the National Historic Oregon Trail Interpretive Center at Flagstaff Hill - a how to find the best stops and hidden gems between cities example.

Fuel costs average $3.50/gal in WY, $3.80 in OR (self-serve banned east of the Cascades – full-service only), with stations every 30-50 miles along US-20, but sparse between Buffalo and Gillette (78 miles). Plan to fill in Thermopolis, Casper, Buffalo, and Baker City.

US-20 is mostly two-lane; I-84 from Ontario to Baker City is a modern interstate. Road quality is good, but winter can close passes – check local forecasts. Cell service is patchy; download offline maps.

In Wyoming, speed limits hit 75 mph, but reduce to 65 in construction zones – hefty fines. Watch for cattle on US-20 near Worland. Oregon's I-84 has rumble strips and clear signage.

For kids, the Wind River Canyon is a natural wonder; in Buffalo, the Jim Gatchell Memorial Museum has frontier artifacts. Pets are welcome at most roadside rest areas – use designated pet exercise areas.

Fatigue management: take breaks every 2 hours – the Powder River rest area (mile 220) is a good stop. The Big Bend Rest Area (mile 290) has views of the Bighorn Mountains.