Roslyn is a city in Kittitas County, Washington, United States. The population was 950 at the 2020 census. Roslyn is located in the Cascade Mountains, about 80 miles east of Seattle. The town was founded in 1886 as a coal mining company town. During the 20th century, the town gradually transitioned away from coal, and today its economy is primarily based on forestry and tourism. The town was the filming location for The Runner Stumbles, Northern Exposure, and The Man in the High Castle.