Have you ever wondered which day you should open your pool? While we can’t give you a definite date for that prospect because it all depends on where you live, we can tell you that there is a holiday that does provide a specific date for opening your pool.

This holiday is called National Pool Opening Day, and it’s observed on the last Saturday in April every year. It’s a day when people can start getting their pool ready for the swimming season. Although we can’t guarantee that this date is when you’ll be able to fully open your pool, we can say that it is the date on which you can begin the pool-opening process.

The History of National Pool Opening Day

This holiday was first created in 2016 by Leslie’s Swimming Pool Supplies—a company that benefits when people open their pools and need to buy pool chemicals. It’s a holiday that has since taken on a life of its own, however, and is celebrated by people all over the world.

Fun Facts About Pools

Below are some fun facts about pools for your entertainment.

• The oldest swimming pool is The Great Bath in Mohenjo-Daro, Pakistan. It dates back over 5,000 years.
• An Olympic-size pool can hold up to 850,000 gallons of water.
• There are an estimated 10.4 million residential swimming pools in the United States.

Observing National Pool Opening Day

On this day, people are encouraged to begin the process of opening their pools. Although in some areas it might be too cold to fully open the pool, there are things that can be done to get the pool ready to be opened.

This includes purchasing the proper chemicals, testing the pool’s water, and cleaning the pool. While you’re getting ready to open the pool, don’t forget to use the hashtag #NationalPoolOpeningDay to spread the word about this holiday online.