which county is castle rock in
Castle Rock, the Gateway to Mount St. Helens, is situated between the Cowlitz River and Interstate 5, located 134 miles south of Seattle and 63 miles north of Portland, Oregon. (Link to map of Castle Rock .) It is the northern most city in Cowlitz County, with a population of 2,120. Spirit Lake Memorial Highway (State Route 504) connects the city to the Mount St. Helens National Monument and Spirit Lake recreation areas â two of the most outstanding tourist attractions in Washington State.