POPULATION: INFO: New Karston, often called "NK" for short, is the largest city in Jackson County, Douglas Island. It is the central city in the New Karston Metropolitan statistical area. This metro area is more often referred to as the Ron River Metro Area. The city is located in the Ron River Valley. The Ron River cuts through the city separating the city into a west and east division. The Evergreen Mountains can be seen from the city. The Pacific Ocean and Ron River mouth are to the south of the city along the waterfront.