Swimming (sport)
Competition pools

World Championship pools must be 50 metres (160 ft) (long course) long and 25 metres (82 ft) wide, with ten lanes labelled zero to nine (or one to ten in some pools; zero and nine (or one and ten) are usually left empty in semi-finals and finals); the lanes must be at least 2.5 metres (8.2 ft) wide. They will be equipped with starting blocks at both ends of the pool and most will have Automatic Officiating Equipment, including touch pads to record times and sensors to ensure the legality of relay takeovers. The pool must have a minimum depth of two metres.

Other pools which host events under World Aquatics regulations are required to meet some but not all of these requirements. Many of these pools have eight, or even six, instead of ten lanes and some will be 25 metres (82 ft) long, making them Short course. World records that are set in short course pools are kept separate from those set in long course pools because it may be an advantage or disadvantage to swimmers to have more or less turns in a race.

Due to waves created by the swimmers, it can be an advantage to swim closer to the center of the pool during a race. Due to this, World Aquatics regulations specify which lane each swimmer competes in based on previous times.

In a ten lane pool this is as follows:
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