Whitefish is the busiest stop on the Empire Builder between St. Paul and Seattle/Portland. Whitefish is the stop for Kalispell (the county seat of Flathead County with over 100,000 residents), Columbia Falls, Bigfork, Eureka, and Southeastern BC. Tourism is major economic force in Whitefish and the Flathead Valley due to its proximity to Glacier National Park, but also is bolstered by the popular Whitefish Mountain (Big Mountain) ski area, Whitefish Lake, and Flathead Lake (the largest natural fresh water lake west of the Mississippi River).