On the tracks above Trout Brook- Thurston County — Thumbnail History (historylink.org)
Thurston County is located in Western Washington, on the southern end of Puget Sound, often called the “South Sound.” It is the eighth smallest county in the state, with a total land mass of 727 miles, but also the eighth most populous county, with a population of 207,355 counted in the 2000 United States Census.