From the guidebook:
At 112.5 m. SATUS PASS (3,149 alt.), is crossed. Beyond the reach of trampling feet, wild flowers bloom among tufts of wild grass.
---Washington: A guide to the Evergreen State
After crossing the Columbia River at Biggs (elev. 200 feet), U.S. Hwy. 97 climbs over the Simcoe Mountains before reaching the Yakima Valley at Toppenish (elev. 750 feet). The high point of this route is at Satus Pass at an elevation of 3107 feet.