There are 3 US Post Offices in Rawlins County serving a total of 2,192 residents equating to 731 residents per post office. It's estimated that approximately 3,499 packages are handled across the 3 county post offices annually. Rawlins County (standard abbreviation: RA) is a county located in the U.S. state of Kansas. As of the 2010 census, the county population was 2,519. The largest city and county seat is Atwood. It was named after Union Civil War General John Aaron Rawlins."