This is marker is located in Helen McCabe/Yakima Canyon State Park on State Route 821 (Canyon Road) at milepost 24.55 just southeast of Ellensburg.
Inland Empire Highway
For thousands of years, Native Americans and, later, wagons traveled from Yakima to Ellensburg using the Shushuskin Trail, over Ellensburg Pass. This was a rough, bumpy, winding trail that begged for an alternative by the mid-1910s, when automobiles began to make their mark on central Washington.
The State Highway Fund, established in 1905, also established the State Highway Department, whose job it was to build, improve, and maintain state roads. The SHD had designated a number of primary routes throughout the state. The "Inland Empire Highway," which began in Ellensburg, extended south through Yakima and Richland, east through Walla Walla, then north through Pullman, Spokane and Colville to the Canadian border. This was officially Primary State Highway #3, a portion of which is today named "Canyon Road."
From 1932, when construction was completed, until 2004, this road was virtually unaltered; it was a narrow stretch of pavement with no crown, made entirely of Portland Cement Concrete. Each lane was constructed of concrete panels 10 feet wide and 14 feet in length. In area where trucks were expected (such as Tjossem's Mill, now Millpond Manor, and the Northern Pacific Railroad Depot at Thrall), heavy-service metal curb guards were installed; these iron rails effectively prevented the concrete from breaking down under the heavy traffic for seventy years.
In 2004, in order to meet modern safety regulations, Kittitas County rebuilt a portion of the Inland Empire Highway, from the Ellensburg City Limits to the mouth of the Yakima Canyon.
This marker is placed here to memorialize the fact that the Inland Empire Highway was a significant part of the first statewide system of motorized vehicle roadways aligned and constructed by the Washington State Department of Highways, August 1932.