How Long is a Mile?

This feels like it should be a simple question to answer. But I cannot tell you how many times I have gotten into (very aggressive) discussions with people when they ask me how many laps are in a mile.

So. In reality a mile is 5,280 feet. That would make it 1,760 yards or 1,609.34 meters.

However, below are the distances used as a competitive mile in swimming:

Short course: 1,650 yards (66 lengths of the pool)
Long course: 1,500 meters (30 lengths of the pool)
Open water: 1,760 yards (or as close as they can get)

Why is this? Why don’t they at least make a short course mile 1,700 or 1,750 yards, so it’d be closer to the real distance? I don’t know, I did not make the rules, don’t kill the messenger.

UPDATE:
Apparently someone dug up the reason why. So if you care…via swimswam:

Swimming pools in the United States, Australia, and the UK were often built in 55 yard distances in the early and middle part of the 20th century. Similar to 440-yard tracks, 55 yard pools were used because races could be made in convenient, even proportions of  a mile (880 yard half mile, 1760 yard mile, etc.). Looking through old records, you’ll notice that there is both a record for the 1760 freestyle and the 1650 freestyle. That’s because, for a long time, the official mile distance in the United States was 1760 yards.

But then things changed.

The AAU (predecessors to USA-Swimming) relented and changed their long course meets from 55-yards to 50-meters in order to better prepare their swimmers for the Olympics. But the United States held firm with its short course pool at 25 yards, instead of the international meters. Large organizations training Olympians could afford the expense of converting their pools to 50 meters (which is about a foot short of a 55 yard pool) or building new ones, but to the tens of thousands of neighborhood and high school pools, this cost would’ve been prohibitive.

In international swimming, beginning with the 1908 Olympics (which were actually swum in a massive 100m pool built inside of a track oval), the 1500m freestyle was a logical standard distance event. At 1.5 kilometers, it made sense to the other 95% of the world that uses the metric system, and sporting fans were already familiar with the 1500m run that was a standard distance in the more familiar track & field discipline.

Once the United States switched to a system of 50-meter long course and 25-yard short course pools, they had to find a way to keep the two systems as similar as possible, so that when its athletes did travel to international competitions, they weren’t at too much of a disadvantage.

And this is where the 1650 freestyle came from. The closest emulation of a 1500m swim in a 25-yard pool is the 1650 freestyle (to be precise, 1500m=1640 yards, 1 foot, and 3.12 inches, give or take), so the AAU likely decided to replace the true old-fashioned mile with a newer, more worldly distance. People were so used to calling this distance the “mile” that the name lived on. So there you have it. It was that crazy Imperial system after all.

Now, as to whether USA-Swimming, the NFHS, and the NCAA should switch from 25 yards to 25 meter short course swimming is a whole different discussion for a different time.