The Historic Columbia River Highway is an approximately 75-mile-long (121 km) scenic highway in the U.S. state of Oregon between Troutdale and The Dalles, built through the Columbia River Gorge between 1913 and 1922. As the first planned scenic roadway in the United States, it has been recognized in numerous ways, including being listed on the National Register of Historic Places, being designated as a National Historic Landmark by the U.S. Secretary of the Interior, being designated as a National Historic Civil Engineering Landmark by the American Society of Civil Engineers, and being considered a "destination unto itself" as an All-American Road by the U.S. Secretary of Transportation. The historic roadway was bypassed by the present Columbia River Highway No. 2 (now Interstate 84 [I-84]) from the 1930s to the 1950s, leaving behind the old two-lane road. The road is now mostly owned and maintained by the state through the Oregon Department of Transportation (ODOT) as the Historic Columbia River Highway No. 100 (still partially marked as U.S. Route 30 (US 30); see Oregon highways and routes) or the Oregon Parks and Recreation Department as the Historic Columbia River Highway State Trail.

The original highway was promoted by lawyer and entrepreneur Sam Hill and engineer Samuel C. Lancaster, to be modeled after the great scenic roads of Europe. From the very beginning, the roadway was envisioned not just as means of traveling by the then popular Model T, but designed with an elegance that took full advantage of all the natural beauty along the route.

When the United States Numbered Highway System was officially established in 1926, the highway became the part of US 30. Since then, modern I-84 has been built parallel to the highway between Portland and The Dalles, replacing it as the main travel route and resulting in the loss of some of the original sections of road.