Summit County is a county in the U.S. state of Utah, occupying a rugged and mountainous area. As of the 2010 census, the population was 36,324. Its county seat is Coalville, and the largest city is Park City. The county was created in 1854 and later organized in 1861. It is so named because it includes 39 of the highest mountain peaks in Utah.The county's mean elevation is 8388ft above sea level, which is the second-highest of any county outside Colorado. Owing to its proximity to Salt Lake City, Park City has acquired a reputation as an upscale getaway, bringing new development to the area.Summit County comprises the Summit Park, UT Micropolitan Statistical Area, which is also included in the Salt Lake City-Provo-Orem, UT Combined Statistical Area.GeographyAccording to the U.S. Census Bureau, the county has a total area of, of which is land and (0.5%) is water.Adjacent counties Rich County (north) Morgan County (northwest) Salt Lake County (west) Wasatch County (south) Duchesne County (south) Daggett County (east) Sweetwater County, Wyoming (northeast) Uinta County, Wyoming (north)