There are 3 US Post Offices in Gilpin County serving a total of 5,148 residents equating to 1,716 residents per post office. It's estimated that approximately 8,217 packages are handled across the 3 county post offices annually. Gilpin County is the second-least extensive of the 64 counties of the U.S. state of Colorado, behind only the City and County of Broomfield. As of the 2010 census, the population was 5,441. The county seat is Central City. The county was formed in 1861, while Colorado was still a Territory, and was named after Colonel William Gilpin, the first Governor of the Territory of Colorado. Gilpin County is part of the Denver-Aurora-Lakewood, CO Metropolitan Statistical Area."