Rarely, you'll find an older, imperial length track that is 440 yards long and exactly four laps to a mile. However, most modern tracks are based on the metric system, meaning each lane is 400 meters long. When it comes to common track workouts (e.g. 400-meter or 800-meter repeats) you'll be following the metric system. But if you want to run a 1 or 2-mile time trial, things get a little tricky. Running four laps on a metric length track will be 9 meters, or 31 feet short of a full mile. That's not a huge discrepancy, but if you're looking to be precise, every step matters! Be on the look out for the marking that designates a full mile.