The Hamilton County Speedway is the oldest speedway in the state of Iowa, opening in July 1910. In 1938, work began on the current location at the Hamilton County Fairgrounds. The semi-banked half-mile dirt track was completed in the spring of 1939, and the first races were held on the track in September of that year. The track is located off of US 20 at exit 140, then 1.2 miles north, then 0.5 mile east on Bank St., then 0.4 mile south on Bluff St.