There are 3 US Post Offices in Iron County serving a total of 23,202 residents equating to 7,734 residents per post office. It's estimated that approximately 37,033 packages are handled across the 3 county post offices annually. Iron County is a county located in the U.S. state of Utah. As of the 2010 census, the population was 46,163. Its county seat is Parowan, and the largest city is Cedar City. The county was created in 1850 and organized the following year. It was originally named Little Salt Lake Valley, and renamed for the iron mines west of Cedar City. The Cedar City, UT Micropolitan Statistical Area includes all of Iron County."