| Summit County Colorado Cities/Towns - Blue River, Breckenridge (County Seat), Dillon, Frisco, Silverthorne |
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Your Ad Here Summit County is a county in the State of Colorado of the United States. The county population was 23,538 at U.S. Census 2000. The county seat is Breckenridge. History Summit County was organized as one of the seventeen original Colorado counties by the First Territorial Legislature on November 1, 1861. It was named for the many mountain summits in the county. ![]() |