The Mississippian was a period of marine transgression in the Northern Hemisphere: the sea level was so high that only the Fennoscandian Shield and the Laurentian Shield were dry land.
The southern terminus of the Vashon Highway is the Tahlequah Ferry Terminal in the Tahlequah neighborhood, connected to the Point Defiance neighborhood of Tacoma by the Point Defiance–Tahlequah ferry.