What is the 4 Mile Challenge?

The 4 Mile Challenge is for swimmers that wish to push themselves that little bit further, and is ideal as a fund-raising option either for Level Water, or a charity of your choice. Swimmers will swim the 1 mile course 4 times throughout the day. 4x Challenge swimmers start their first mile early at 08:30 to allow time to complete all 4 miles. You will need to allow time to eat and drink, we suggest you bring enough food to last you through all 4 swims, as the queues for the food concessions may not fit with your timings. To enter this challenge you need to be sure that you can swim AND walk/jog a mile within 75 minutes. At the end of each mile, swimmers will need to walk back to the start (approx 1 mile) before starting their next mile. After your final leg you will receive a finishers’ medal and a well-earned rest.

What is the Suits vs Skins Challenge?

In a bid to once and for all determine the performance boost given by wetsuits, competitors will have the opportunity to take part in the “Suits v Skins Challenge“. Anyone who wants to take part in this challenge will need to swim the Mile twice: once with a wetsuit and once without. The winner will be the person with the fastest combined time for the two miles – but everyone taking part will see what difference swimming in a wetsuit really makes. How to Enter: Simply select Suits vs Skins on the registration form. You should wear your wetsuit for the first swim, and swim non-wetsuit for the second.

Are children allowed to swim without an adult?

If your child is aged 12 or under, you will need to make sure that they have either an accompanying adult swimming with them, or walking the tow-path alongside them. When you register your child for the event, you will be asked to confirm that you have understood this. Children aged 13+ do not require this, however we very much hope that you will be supporting your child throughout their swim. You can walk alongside all the way. We also ask you to be sure that your child has the capability to swim in the event that you enter them in.

What temperature will the water be?

As with any outdoor swim event the water temperature will depend upon both the outside temperature and the quantity of rainfall in the days and weeks running up to the event. It is therefore very difficult to predict. Based on previous years, in the middle of July we would expect the water to be between 18 and 21 degrees centigrade.

Can you guarantee the water quality?

We test the water throughout our season (June – August) to get an idea of the overall water quality on this stretch of the Thames. Over the past 5 years, 93% of our tests have come back as good or excellent measured against European Bathing Water standards. However due to the nature of moving water, and the fact that a water sample takes several days to cultivate, we cannot guarantee that the water quality on the day of the events will be satisfactory. Swimming in open water carries risks. Water quality is variable as is an individual’s tolerance to contaminants.

Outdoor Swimmer Henley Swim Festival

From Henley Swim

Friday 11th – Sunday 13th July 2025 Past event

09:00

Henley-on-Thames

Event summary

Join us for the Outdoor Swimmer Henley Swim Festival, hosted by Henley Swim, from Friday, July 11 to Sunday, July 13, 2025, in the picturesque Henley-on-Thames, Oxfordshire. This exciting weekend is a celebration of open water swimming, set against the stunning backdrop of the Thames. Whether you are a novice looking to dip your toes or an experienced swimmer aiming to conquer longer distances, there’s a challenge for everyone, with options ranging from the 200m Splash, perfect for ages 8 and up, to the invigorating 4 Mile Challenge.

The festival promises more than just swimming; it’s a vibrant gathering for the whole family! Enjoy a bustling event village filled with exhibitors, retailers, and experts sharing their love for the sport. Make the most of your experience with delicious food and drink, live music, and entertainment, all while camping at the beautiful Temple Island Meadows, just steps from the riverbank. Meet the Outdoor Swimmer Magazine team and engage in various activities hosted by the charismatic Sports Presenter Ben Croucher. Don’t miss this chance to immerse yourself in the exhilarating world of open water swimming—mark your calendars for an unforgettable weekend!

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The Outdoor Swimmer Henley Swim Festival is a weekend celebration of open water swimming, set in the most stunning location on the banks of the Thames just outside Henley. This event offers swimming challenges with distances to suit novice and expert swimmers alike.

Alongside the swimming, a bustling event village is packed full of exhibitors, retailers and experts all together in one place – giving you access to everything you need to know about this adventurous sport. We welcome the whole family, with camping available on Friday and Saturday nights on site at Temple Island Meadows - you won't find a spot closer to the river!

With acres of space, delicious food and drink, a chance to meet the Outdoor Swimmer Magazine team, music, entertainment and other activities, all hosted by Sports Presenter Ben Croucher, this really is the perfect event for every swimming enthusiast.

There is nothing quite as exhilarating as swimming in open water, a sport that continues to grow around the world and which offers both physical and mental benefits. Our swim events range from the 200m Splash - suitable for ages 8+, to the 4 Mile Challenge. Children under 8 can swim in the supervised Lido, giving them a chance to experience the river in a safe and controlled environment.

Location

Remenham Lane, Henley-on-Thames, RG9 3, United Kingdom

Henley Swim

Henley Swim has a range of open water swimming events, covering distances from 200m to 13km, at different times of day, upstream and downstream, wetsuit and non-wetsuit, from age 8 to 88. We cater for the requirements of everyone from the novice to the experienced swimmer.

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Since 2015

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Avg. review 4.8

Outdoor Swimmer Henley Swim Festival

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