Snohomish was founded around 1858 by Emory C. Ferguson, E. F. Cady and others. It was originally known as Cadyville, but changed its name to Snohomish City in 1871. The name Snohomish comes from the name of the dominant local Native American tribe, whose meaning is widely disputed. One of the first inland cities in the Puget Sound region, Snohomish was built where a planned military road connecting Fort Steilacoom and Fort Bellingham was set to cross the Snohomish River.

Monroe was once the site of the Great Northern Railway's botanical gardens where fresh flowers for their passenger trains were once grown. Each day these flowers would be loaded aboard the Western Star for distribution throughout the system so that each dining car passenger might have fresh flowers with their meal.
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Index -- Thumbnail History HistoryLink.org Essay 9143 :

The area now called Ballard was settled by the Dxʷdəwʔabš (Duwamish) Tribe after the last glacial period[4][circular reference].[5] There were plentiful salmon and clams in the region.[6] The U.S.

Seattle's location, harbor, and commercial development made it a logical place for the Great Northern's terminus, and Hill had the good sense to engage the persuasive and influential Thomas Burke as his local agent. Having previously achieved the creation of Railroad Avenue, Burke had little difficulty persuading the city council -- over the vociferous objections of the Northern Pacific -- to give the Great Northern a 60-foot right-of-way down the middle of the wood-planked roadway.