But so much more than just a race™
The iconic English Channel distance of 33.3km, spread over a four day long weekend in breathtaking locations. World class safety, premium packages and training support from the day you sign up.
UltraSwim 33.3 is an Epic Adventure Swim Race™ covering 33.3km, the historic English Channel distance, split across five to seven point to point open water swims (we hate laps) over four days in warmer water locations (a 'half Channel' 17km option exists). So far held in Croatia, Switzerland, Greece, Spain, Montenegro and the Caribbean, based at premium hotels, with world class safety cover, premium support, a complete preparation programme and a diverse community that ranges from mid teens to eighties, usually more women than men.
From competitive Masters swimmers, triathletes and swimrunners to leisure and wild swimmers simply aiming to complete the distance. From a required pace of just 2km/h, any determined swimmer can do it. Come in a group or alone, everyone leaves with new friends for life. Award winning, all inclusive packages start from 1,800 Euros (€750 for our 2 day Compact format)

The iconic English Channel distance spread over five to seven swims. Choose the full 33.3 CLASSIC, or the 33.3/2 BUILD 'Half Channel' which caps each swim at 5km. Life-changing for many.

Swiss precision event organisation. Boat and kayak safety cover provided on every swim. Daily briefings on conditions, route and pace. Experienced and dedicated team looks after you from the moment you join.

Whether you come on your own or with a club, you will find your tribe, and make new lifelong bonds over 4 days of highs and lows as you reach for that 33.3 Finisher droplet

All iconic, each with their own challenges and beauty - Croatia, Switzerland, Greece, Montenegro, Spain and the Caribbean. From May to December, designed to fit your season and time constraints.

Event Format

Four Days. One Epic Journey
Every edition follows the same simple rhythm over a long weekend. Early starts for the best weather and safety, a post swim refuel, recovery massage*, and return to the hotels for an easy afternoon to rest or explore, and evenings together cementing new friendships.

World Class Swimming
The distances build gradually from 4km, leading up to a 10km (or maybe a bit more) marathon swim on day three, weather permitting. You'll wrap up the final day with a scenic, celebratory course of c.4km. You will definitely have tired days, but you'll also have moments where you feel like Superman. Whenever doubt creeps in -on or off the water -the incredible energy of the group will carry you forward.

An Experience You'll Never Forget
The overall experience will leave a positive mark on you - and for many, it will even be life-changing. You'll give your very best whether you finish every leg or not, because our aim is to send you home a better swimmer, a better person, or both.

Why swimmers choose us
Yes its organised as a race - for some winning will indeed be their aim. For most though, it will just be about finishing, at whatever pace they can. It will sometimes feel like a tough challenge, other times the perfect swimming holiday, and at the end for many a life-time acheivement (and almost everyone has come back for a further edition so far). Unlike most races, your non-swimming partner accompanying you will really feel they are part of your team.
Nine short questions, about two minutes of your time. We read your submission, then share information with you to help you select the right event for you.
Nothing great is easy. Choose your event and secure your spot with a fully refundable €500 deposit. Your adventure of a lifetime starts here.
Book NowIf you have been holding back because of your partner, your kids or your group of friends, the answer is usually simpler than you think. UltraSwim 33.3 was built around the idea that the people who matter to you should travel with you. Family rooms at every host hotel. The F3 (Family, Friends and Fans) Supporter and Activity package ensures your loved ones feel part of the team, supporting you, but not forced to watch you swim for hours on end! By the end of the four days, most say the trip ended up being as much about their family as about them.
On the question of what is stopping you, the honest answer in most cases is nothing real. Our youngest participant to date is 14. Our oldest in her eighties. The median age across the calendar is a little over 50. The community runs from career swimmers to people who picked up open water in their fifties because something in their life had shifted. Most swimmers say the part they were most worried about, the distance, the cold, the kit, the time off work, turned out to be the part they cared least about by day three. What stayed with them was the people they swam alongside and the version of themselves they met somewhere on the second swim.
It is a timed open water swimming challenge covering the English Channel distance of 33.3km, spread over four days and five to seven swims, in locations such as Montenegro, Croatia, Greece, Spain, Switzerland and the Caribbean. A point to point format (we hate laps), an epic adventure swim race that brings like-minded determined swimmers from all over the world together, all chasing the same 33.3 Finisher droplet.
No, not as fast as you probably think. The cutoff is based on never more than 2km/h, eased further for the conditions on the day if logistics permit. As a guide, you should be able to swim 2.5km in a one hour pool non-stop swim and have completed at least one 4 to 5km open water swim in training. If you don't complete one of the swims, you can still carry on and finish the rest of the event.
Most of our swimmers have never taken on anything like this before. The distance is split across five to seven swims over four days, building step by step to a 10km day when you are stronger and more confident on day 3 normally. With good preparation in the months beforehand, and the collective energy of the 33.3 family around you, any competent swimmer is capable of it. A majority of participants have never swum more than 4 or 5km in one go before attending.
Wetsuits are permitted but not required. You can switch to a wetsuit during the event, though your ranking category will stay as wetsuit from then on even if you return to skins. About half our swimmers wear wetsuits, depending on the venue and the water temperature, but we do not put restrictions on when you must or must not wear a wetsuit. Long endurance swims cannot be treated like short course triathlon swims (where the rules dictate whether you wear a wetsuit or not)
Your entry package includes a lot, even at our entry level ULTRA package you get four nights accommodation at the host hotel, early morning race day breakfasts, a refuel lunch on each race day, full safety cover on the water and professional support throughout, a prizegiving on final day. There are options for extra nights, upgrades and single occupancy, as well as our Friends and Family Supporter Package (they will feel totally part of your team and the event - without being bored by it!). Secure your place with a 500 euro reserve payment, fully refundable for up to 30 days, no questions asked.
Safety is the paramount consideration throughout. Alongside transfer boats that stay with the swimmers, kayaks and paddle boards accompany you and wait at key turning points, so you can usually see one ahead or behind. There is a Race Director, RIB and a dedicated medical support boat, and every swimmer carries a tracker so we always know where you are. Of course by its very nature open water swimming in a point to point format is not without risk - but we work hard to make sure you are both safe AND feeling safe at all times. Careful weather monitoring, flexible course plans pre-authorised with authorities, and race marks all help you navigate safely - we also start early mornings on purpose to be swimming with the minimum of boat traffic in the vicinity of the racecourse.
Yes, and they are very welcome. There is a package built for non participating partners (we call them NSP - Non-Swimming Partners) that makes them part of the experience without watching too much swimming, with options for your partner or family alongside your entry. Many swimmers come as a couple or a family, and most say the trip ends up being about far more than the race. The Supporter and Activity package for F3 (Family, Friends and Fans) is an add-on package that pretty well everyone signs up to as accompanying partners. It includes boat and land transport to starts and finishes, welcome drinks and prizegiving, post swim refuel lunches with your partner when timing permits, and even at most events swimming the final few hundred metres together (if they are planned as untimed).
33.3 CLASSIC is the full English Channel distance of 33.3km across the four days, the big monster option. 33.3/2 BUILD is the half channel option, covering half the distance (around 17km) a strong choice if you are building towards the full challenge. Daily cutoff times apply to both, both based on 2km/h. The 33.3/2 BUILD option is a non-competitive format, without podium prizes or rankings (although where the swims are the same as the CLASSIC, you will get a time to compare with others). Places on the BUILD are limited to 10 per event usually.