US 197 begins at an intersection with US 97 at Shaniko Junction in Wasco County, located between the cities of Madras and Shaniko in Central Oregon. The highway, a continuation of The Dalles-California Highway No. 4, travels northwest over the Criterion Summit and down along Stag Canyon through the community of Criterion towards Maupin. US 197 crosses the Deschutes River and a BNSF rail line on a warren truss bridge, becoming Deschutes Avenue as it passes South Wasco County High School and through the city of Maupin. The highway continues west into the Juniper Flat and intersects Oregon Route 216 (OR 216), designated as Wapinitia Highway No. 44, and forms a concurrency. US 197 and OR 216 travel north and northwest to Tygh Valley, where OR 216 leaves the concurrency and heads east on Sherars Bridge Highway No. 290 towards Grass Valley. The lone highway continues north up Butler Canyon onto Tygh Ridge, passing through the Tygh Grade Summit. US 197 travels east of Dufur and down into the Columbia River Gorge, entering the city of The Dalles. The highway begins a concurrency with US 30, traveling north over an east-west BNSF rail line to a diamond interchange with I-84. US 197 leaves the interchange and the state of Oregon on The Dalles Bridge, crossing over the Columbia River into Washington. An ODOT survey measuring traffic volume for any average day of the year, expressed in terms of annual average daily traffic (AADT), was conducted in 2011 on US 197 and calculated that the busiest section of the highway in Oregon was on The Dalles Bridge, serving 5,800 vehicles, while the least busiest section of the highway was north of its terminus at US 97, serving 390 vehicles.