There are 3 US Post Offices in Cameron County serving a total of 5,035 residents equating to 1,678 residents per post office. It's estimated that approximately 8,036 packages are handled across the 3 county post offices annually. Cameron County is a county located in the U.S. state of Pennsylvania. As of the 2010 census, the population was 5,085, making it Pennsylvania's least populous county. Its county seat is Emporium. The county was created on March 29, 1860, from parts of Clinton, Elk, McKean, and Potter Counties. It is named for Senator Simon Cameron."