US 97

US 97 was part of the original US Highway System of 1926.

This highway starts at the US-Canadian border and heads south along the Okanogan Valley via Oroville, Tonasket, Omak, and Okanogan to the vicinity of the confluence of the Okanogan and Columbia Rivers. The highway then follows the Columbia downstream via Brewster and Pateros.

Hugo is a locale a few miles northeast of the City of Chelan. Although the original plan was for US 97 to continue along the Columbia to Chelan Falls, cross the river to Beebe, and then head south along the east side of the river to East Wenatchee, the "temporary" route of US 97 stayed to the west of the river, passing through Chelan Falls and Entiat. There was a private bridge across the Columbia between Chelan Falls owned by the Beebe Orchards. The road heading south from Beebe was primitive. In 1937, the state legislature designated the route via Chelan and Entiat as Primary State Highway (PSH) 10. This became permanent US 97. At the same time, the route crossing the Columbia at Chelan Falls heading south to Orondo was designated as Secondary State Highway (SSH) 10-D.

Fast forward to 1962. The state replaced the private bridge at Chelan Falls-Beebe with a modern bridge. In the following years, SSH 10-D was improved. As part of the 1964 state highway renumbering, SSH 10-D became SR 151. In 1985, the state completed a realignment of SR 151 more directly between Chelan Falls and Hugo. WSDOT petitioned AASHTO to move US 97 to the original alignment as first approved in 1926. AASHTO approved in 1987. The route via Chelan and Entiat became Alternate US 97.

US 97 joined US 2 at Olds Station (now within the city limits of Wenatchee) northwest of the confluence of the Wenatchee and Columbia Rivers. This is now the general location of the south end of alternate US 97. Since US 97 was rerouted between Hugo and the Wenatchee area in 1987, US 97 now joins US 2 at Orondo. US 2 and US 97 run coincident from Orondo to Wenatchee downstream along the Columbia River, then westerly upstream along the Wenatchee River via Cashmere to a junction near the confluence of the Wenatchee River and Peshastin Creek. From this junction, US 2 heads westerly to Stevens Pass and Everett. US 97 heads south along Peshastin Creek to Blewett Pass and I-90 in Ellensburg. US 97 and I-90 run coincident from Exit 106 to Exit 110, where I-82 begins and US 97 joins I-82. The original route of US 97 headed south from Ellensburg to Yakima via the Yakima River Canyon. When I-82 opened from the Ellensburg area to the Yakima area in the hills east of the canyon, US 97 was moved to the freeway. The route through the canyon became SR 821.

US 97 originally passed through the center of Yakima and Union Gap. US 12 (originally US 410) joins US 97 and I-82 at Yakima. I-82 in the Yakima-Union Gap area was but in stages that opened between 1962 and 1968. US 97 was shifted to the freeway when it opened. South of Union Gap, US 97 originally continued southeast coincident with US 410 (US 12) to Buena. At Buena, US 410 (US 12) continued Southeast down the Yakima Valley to the Trip-Cities. US 97 headed south from Buena to Toppenish. SSH 3-A provided a more direct connection from Union Gap via Wapato. Added to the state highway system in 1937, SSH 3-A went down the southwest side of the Yakima Valley from Union Gap via Toppenish to Prosser. PSH 3 (US 410, later US 12) was on the other side of the valley and passed trough Zillah, Granger, Sunnyside, and Grandview. At first this roadway was narrow, 2 lanes, and passed through cities along the way. In the early 1950s, work to relocate SSH 3-A was started, with partially-controlled access bypasses of Wapato and Toppenish constructed. In 1954, SSH 3-A from Union Gap to Toppenish became Alternate US 97. When the current state highway numbering was first posted in 1964, US 97 was rerouted from Union Gap via Wapato to Toppenish. The highway from Buena to Toppenish and SSH 3-A from Toppenish to Prosser was renumbered SR 22.

The highway over Satus Pass had not been constructed when US 97 was first designated. A temporary route heading southwest from Mabton in the Yakima Valley over the Horse Heaven Hills via Bickleton to Goldendale was established. This route is now a county road. The Satus Pass highway between Toppenish and Goldendale opened to traffic around 1931. US 97 passed through Goldendale until a limited access bypass was completed in 1978. The highway going downhill from Goldendale to Maryhill on the Columbia River used an early paved road (constructed circa 1910 - now private) before the present alignment was constructed. US 97 originally crossed the Columbia via a ferry from Maryhill to Biggs, Oregon. A bridge replaced the ferry in 1962. That bridge was named for Sam Hill in 1964. Sam Hill built Maryhill mansion, now a museum, and the nearby Stonehenge replica. He created the Washington State Good Roads Association in 1899, which advocated for the creation of the state agency that is now the Washington State Department of Transportation.