Ultra Swimming

Ultra Swimming is long-distance swimming, outside the confines of a swimming pool. Since ultra swimming typically takes place in lakes and oceans, it is often referred to open-water swimming.

Interesting Fact:

It takes 70.4 (round up to 71) laps in a 25 yard pool to swim a mile
to figure this out: the number of yards in a mile = 1760 divide by 25 = 70.4

Just note that a LAP is down and back, which is 50 yards. 1760 divide 25 yards is 70.4 LENGTHS, not laps. It is approximately 36 laps in a 25 meter pool to swim a mile.