There are 8 US Post Offices in Fremont County serving a total of 46,564 residents equating to 5,821 residents per post office. It's estimated that approximately 74,321 packages are handled across the 8 county post offices annually. Fremont County is one of the 64 counties in the U.S. state of Colorado. As of the 2010 census, the population was 46,824. The county seat is Ca\u00f1on City. The county is named for explorer and presidential candidate John C. Fr\u00e9mont. Fremont County comprises the Ca\u00f1on City, CO Micropolitan Statistical Area, which is also included in the Pueblo-Ca\u00f1on City, CO Combined Statistical Area. Fremont County is also home to 15 prisons. ADX Supermax, the only federal Supermax prison in the United States, is in an unincorporated area in Fremont County, south of Florence. As of March 2015, Fremont County leads the nation among all counties as the one with the largest proportion of its population incarcerated, with 20% of people residing in one of the county's prisons."