Harker's Run (or Harkers Run, as shown on federal maps) is a stream originating in Preble County, Ohio. Harker's Run drains into Four Mile Creek on the eastern edge of the campus of Miami University in Oxford just north of where the Trenton Oxford Road crosses Four Mile/Talawanda Creek. The stream flows roughly from north to south, and is approximately 5.5 miles (8.9 km) in total length. The elevation at the mouth of the stream is 775 feet (236 m) above sea level. At its highest point, the stream is at approximately 1,000 feet (305 m) elevation.