Historic highways

Learn about historic highways throughout the state.

Federal and state laws and regulations mandate that the transportation project development process take into consideration cultural resources that may be affected by project activities. This includes impacts to roadways at least 50 years old and deemed significant according to the National Register of Historic Places (NRHP) criterion for listing. The Washington State Department of Transportation (WSDOT) maintains an inventory of highways that have been evaluated for the NRHP.

WSDOT recognizes the historical significance of roads and highways in Washington State and effort is underway to identify and inventory historic roadways eligible for the NRHP. The evaluation methods developed by WSDOT, and described in the Guidelines for Identifying and Evaluating the Historic Significance of Washington State Highways (PDF 57KB) focus on engineered features that reflect the historic character of a roadway, including the original alignment, road prism and site distance. Unemployed civilians and inmate work crews built many of Washington’s early roads and state highways under the federal relief programs of President Roosevelt’s New Deal. Segments of highway that are representative of early twentieth century highway engineering and design provide the experience of traveling on a truly historic roadway.

Highways

Interstate 5 (I-5)

The Weedin Place Nuclear Fallout Shelter was built as a prototype in 1963 to be the model for countless similar shelters that would be installed nationwide under interstate highways. The fallout shelter supports the southbound lanes of I-5 and is considered a feature of the federal interstate highway system. Learn more in this publication: Lifeboat Ethics’ under the Interstate: Seattle’s Prototype Highway Fallout Shelter" (PDF 857KB) by Craig Holstine.

SR 520

Learn about 13,000 years of the landscapes, communities and industries along the SR 520 corridor across Lake Washington. This documentation was developed as mitigation for the SR 520 Bridge replacement and HOV Project: 520history.org.

SR 99: Alaskan Way Viaduct Replacement

This report Review and Evaluation of Common Deep Subsurface Archaeological Investigation Methods (PDF 7,613KB) was developed as a mitigation commitment for the Alaskan Way Viaduct Replacement Project. It evaluates considerations for identifying archaeological deposits that may be buried at depths greater than conventional shovel probes may reach.

Historic Highway SR 11, Chuckanut Drive, MP 9 to MP 19.92
Skagit and Whatcom Counties

Neah Bay Road, Secondary State Highway 9A State Route 112

Sedro-Woolley to Jct. SR 542, MP 58.4 to MP 79.4

Sunset Highway, Renton-Issaquah Road SR 900 MP 15.15 to MP 20.08

Learn about two sections of US 101 that have historical significance.

You can find interpretive historical highway markers along state highways and scenic byways throughout Washington. Use the map and list on this page to find marker locations.

8,683 animals crossed the Snoqualmie Pass East Project area

as recorded by WSDOT and partners in 2020 and 2021.

46% increase in Amtrak Cascades ridership to 251,000 passengers

in 2021 compared to 172,000 in 2020.

Nine wetland and stream mitigation sites across 32.7 acres added

to our monitoring program in 2021 to help offset climate change impacts.