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SatApr 26

National Pool Opening Day – April 26, 2025

National Pool Opening Day is a popular holiday that Americans celebrate on the last Saturday in April. This year, it takes place on April 26. Because swimming is part of making summers memorable, it’s important that pool owners keep them clean, and ensure that they’re safe for pool parties with family, neighbors, and friends. Apart from providing a place to socialize, swimming pools also encourage physical activity. By keeping your pool’s acidity and alkalinity levels in check, you ensure that it’s ready for you to enjoy a swim throughout the summer.

History of National Pool Opening Day

National Pool Opening Day reminds pool owners and swimmers all across the U.S. to make their pools summer-ready and make them safe to enjoy during warmer months. Swimming pools help people relax, practice their swimming and provide the opportunity to interact with family and friends. National Pool Opening Day was founded by Leslie’s Swimming Pool to highlight the importance of pool safety and hygiene.

Roman, Assyrian, and Greek warriors were taught to swim as part of their martial training. In 1828, indoor swimming pools became popular in England as St George’s Baths was opened for locals. Swimming was included in the Olympics as a sport in 1896 but only males could participate and it was only in 1912 that women were also allowed to contest. Some common swimming styles, at the time, were sidestroke, breaststroke, backstroke, and crawl, and for each competition, the swimming distance was different.

The first person to swim across the 20-mile width of the English Channel was merchant navy captain, Matthew Webb in 1875. He crossed it in 21 hours and 45 minutes having to swim against tidal currents. The first woman to succeed in this feat was Gertrude Caroline Ederle, a competitive swimmer from the U.S. in 1926 for whom it took only 14 hours and 31 minutes.

Today, swimming has become so popular that there are swimming pools in schools, colleges, and universities where students are trained.

National Pool Opening Day timeline

The First Guide on Swimming

Nikolaus Wynmann writes the world's first swimming guide

Competitive Swimming Becomes Popular

Competitive swimming gains popularity in Europe

Matthew Webb Sets a Record

Webb swims from Dover, England to Calais, France in 22 hours

Backstroke Swimming

Backstroke swimming becomes a part of the Olympics

National Pool Opening Day FAQs

What day is National Pool Day?

National Swimming Pool Day falls on July 11 to celebrate the sport of swimming and encourage everyone to practice this therapeutic water sport.

What month is best to open a pool?

March is considered the best month to open a swimming pool.

What was the first swimming pool?

Swimming pools have been in use since ancient times. The oldest swimming pools in known history were being used by the people of the ancient Indus Valley civilization in 2600 B.C.

National Pool Opening Day Activities

  1. Organize a pool party

    If you love swimming and have a pool at home, arrange a pool party for your family and friends. Prepare some refreshing beverages to serve to your guests and decorate with beach balls and colorful pool noodles.

  2. Deep clean your swimming pool

    Celebrate this National Pool Opening Day by deep cleaning your swimming pool. Drain out the old water and refill your pool with fresh water. Frequently remove the leaves from the surface and invest in a pool vacuum to remove the dirt from your pool's floor.

  3. Improve your swimming

    If you want to improve your fitness, then swimming is a great form of exercise to start this National Pool Opening Day. Swimming is recommended for people who can’t perform strenuous workouts. Swimming is equally beneficial for our mental health and those who suffer from chronic stress and anxiety are often advised to swim as it relaxes the mind and body.

5 Facts About Swimming That Will Blow Your Mind

  1. A unique world record

    Stig Severinsen can hold his breath underwater for 22 minutes.

  2. The oldest stroke

    The oldest stroke in swimming is breaststroke.

  3. A centenarian swimmer

    Mieko Nagaoka is the first centenarian to complete the 1500m freestyle swim.

  4. Shaving and swimming

    Shaving body hair can help swimmers improve their performance

  5. A full-body workout

    Unlike other sports, swimming uses all the muscles in the body

Why We Love National Pool Opening Day

  1. It prevents recreational water illnesses

    Besides hygiene, proper cleaning and maintenance of swimming pools keep them safe to be in, especially kids and seniors who are more vulnerable to waterborne diseases. Regular cleaning of the pool also helps to prevent the growth of aquatic bacteria and mold that grows in pools.

  2. It motivates people to stay fit

    National Pool Opening Day encourages people to clean their pools and use them to stay fit and active. Swimming is beneficial to seniors who suffer from arthritis and cardiovascular diseases. It improves strength and tones muscles without putting excessive pressure on your body. Swimming is a full-body workout and those who want to maximize the advantages of swimming can opt for aquatic yoga to relax.

  3. It reminds people to check their pool water

    Maintaining the right balance of chemicals in water is what will keep it crystal clear. High amounts of chemicals, such as chlorine or pool acid, in the water, are harmful to our skin, eyes, and ears.

National Pool Opening Day dates

2022April 30Saturday
2023April 29Saturday
2024April 27Saturday
2025April 26Saturday
2026April 25Saturday

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