Happy 110th Anniversary I-90 Snoqualmie Pass aka The Sunset Highway

Happy Birthday to 1-90 Snoqualmie Pass.

July 1, 2025 marks the 110th anniversary dedicating the state of Washington's first roadway through the Cascades.

It was July 1,1915 when the Sunset Highway through the mountains over Snoqualmie Pass was dedicated by Gov. Ernest Lister.

The origins of the route were an old wagon road between Seattle and Ellensburg built in 1887, following the path of a Native American trail that existed for hundreds of years.

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According to Cassandra Tate at HistoryLink.org, Henry Yesler, one of Seattle's founders,  led an effort 8 years earlier to make improvements to the route by offering his sawmill as a prize for winning a lottery to fund construction.

They sold tickets and raised about $30,000 or the equivalent to $1.1 million in today's dollars.  But the lottery was deemed illegal and it's believed Yesler pocketed the proceeds.

Further interest to create a passable road was dimmed once the Northern Pacific Railway through the Cascades was completed in 1883 and began carrying most of the travelers and freight.  The Ellensburg based Seattle & Walla Walla Trail and Wagon Road Company tried to maintain the old wagon road but it fell into neglect without much traffic.

The impetus to create what we now travel on I-90 Snoqualmie Pass was likely an automobile race planned for the 1909 Alaska-Yukon-Pacific Exposition in Seattle.  King and Kittitas County funded a project to regrade the old wagon road and clear debris and add some bridges.  When about 150 cars traveled the route to attend the Exposition, state legislators were satisfied the road was viable and provided the appropriation to start construction.

What was originally called "Primary State Highway 2" officially opened six years later on the 1st of July, 1915

Travel  through the Cascades was now possible in record time.  Author Clarence Bagley wrote in 1916 publication of Seattle history that Washington Gov. Lister made the journey from Olympia to Snoqualmie Pass in a few hours traveling by car.  Bagley noted the then Territorial Gov. Marshall Moore needed days to make the same trip by horseback in 1867.

Today, I-90 follows the Sunset Highway route over Snoqualmie Pass and extends east all the way to Boston, MA but the original Sunset Highway was later rerouted just east of Cle Elum at Teanaway and north over the Old Blewett Pass Highway along U.S. Highway 97 and into the Wenatchee Valley.

From there, the Sunset Highway proceeded along the Wenatchee River to East Wenatchee, and headed north up the Columbia River to Orondo, and onto Spokane on what we know as U.S. Highway 2.