Tractor pulling involves the competition of modified farm tractors. Competitors pull a heavy sled down a course measuring at least 320 feet (distances vary by location). As the sled is pulled forward, the weight slides forward, making it harder and harder to pull.
Those who can pull the sled the full distance advance to the next round, with the weight of the sled increased. A winner is declared when less than two tractors complete the full distance. These events are common at state and county fairs in agricultural areas of the United States.
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