Park Jefferson Speedway is a dirt racetrack based on the north side of Sioux City, Iowa. Park Jefferson was founded in the mid 1980's by Ted Carlson as the cornerstone of his racing empire. Park Jefferson rose to prominence as one of the top racing facilities in the area, featuring Super Late Models and also touring specials with Outlaw Sprint cars from the NCRA. In 2014, Park Jefferson Speedway came under the umbrella of A to Z Promotions.
Park Jefferson Speedway is home to weekly IMCA Racing featuring 6 classes of IMCA Race Cars each and every Saturday spring, summer and fall. In addition, Park Jefferson hosts Championship Sprint Cars, Super Late Models and more.