Why 33.3?
We have adopted the iconic English Channel distance of 33.3km, which is the theoretically shortest distance of the English Channel crossing from Dover to Calais that Captain Webb swam in 1875.
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We chose a number that carries history, right back to 1875.
33.3km is the Dover to Cap Gris Nez crossing, the benchmark every Channel swimmer is measured against. Swim it and you join a line that runs all the way back to the first English Channel crossing by Captain Matthew Webb.
151 years on from Webb's 1875 crossing and 100 years since Gertrude Ederle became the first woman to swim the channel, 33.3 is a distance recognised globally.
A 33.3km swim in one go would be out of reach for most people. Spread across four days it becomes a series of swims that hit the sweet spot between challenge and achievability. You build up through the long weekend and take on the longest swim when you are at your strongest mentally and physically.
It's not for everyone, but anyone can do it.
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.
The maths. Four days, five to seven swims, one iconic distance. Here is how the kilometres add up across the long weekend (subject to weather conditions and local variations - this is a generic guide)
Day one · TWO SWIMS 8 to 9km TOTAL
Find your flow
We usually start off with two swims on day one which is the perfect way to start your 33.3 journey. We break the distance into two manageable steps, giving you time for a brief refuel in between.
It is also your chance to settle into the experience, calm your pre-event nerves, adjust to the water conditions and find your tribe in the water
Day two · around 8km
Build the single swim distance
By day two, the distance steps up. You'll feel a little tired and sore from the first day perhaps. 'Over-compensation' will hold you back as your brain asks what are you doing to yourself?!
After day one, you will know more about how your body will react, your energy and how to cope with the conditions. You will have in your mind that day 3 is the marathon stage - but you'll push on through and build confidence that you can do this
Day three · 10km
The marathon swim
Your brain finally gets it - you're not stopping yet - once you are in the water you feel stronger, mentally and physically, than ever before - even if a little sore! This is the moment where 33.3 becomes real. It's a true test of endurance but you won't be starting from zero. This is what you have prepared your mind and body for. For many it will be your longest ever swim at 10 and sometimes 11km. But you will be smiling on that finish line when you know that you can make the 33.3.
Day four 4-5km
Finish as a 33.3'er
After the marathon, you will feel like you can do anything! Day four brings the distance back down giving you space to recover from day three while enjoying the final swim of your 33.3. This swim is about soaking it all in, the atmosphere, the amazing people and the incredible achievement of making it this far. Although it sometimes does provide some surprises - but ones you've learnt how to cope with now.
Enjoy the final kilometres, you've earned them - and that finish line champagne!
Thinking about your first UltraSwim 33.3 but not sure where to start? You are in good company. Almost everyone asks the same handful of questions before they commit, usually about the distance, the cost, and whether they are ready. We have answered them straight, so you know exactly what you are signing up for before you line up at the start.
No. A clear majority of swimmers at UltraSwim 33.3 events have never swum more than 4 or 5km in a single open water swim before they line up at the start. And that's totally fine! The four day format spreads the 33.3km into manageable daily swims, with a 10km marathon swim on day three when you are at your strongest.
All inclusive packages start from less than €1,800 and cover accommodation, world class safety, support and the full four day swim. A €500 deposit secures your place and is fully refundable within 30 days. Exact pricing is shown on each event page and via our price calculators
Yes. Partners are VERY welcome whether they swim or not. Non-swimming partners (we call them NSPs!) can join the trip and do their own thing - OR as most do, be there as part of the F3 Supporter and Activity package (friends, family and fans), with plenty of exciting activities while you are in the water, your partner will see you on the route, meet you at the finish line so you can spend the rest of the day together. As well as being able to join the social events and prizegiving as part of this great package that will make them feel part of your team at the event, but without subjecting them to the same timing (no early mornings!) or hours of watching swimming...they will also at most events get the chance to complete the final few hundred metres WITH YOU!
The long weekend format is designed to reduce time off to the minimum. Maybe you can do a remote/travel work day on the Thursday, and even the Monday afternoon once we're done if you need to keep the days off to the minimum. But ultimately yes the four day event plus travel either side can mean 5 or 6 days in total - of which 2 are the weekend.. Many extend the trip to enjoy the location, and add some extra nights through us, or head off doing their own thing. Exact dates for each event are on the event pages.
Captain Webb is your go-to guide for everything UltraSwim 33.3. Whether you’re wondering about an event, preparing for your swim, travelling to a location or simply looking for more information, Captain Webb is here to help - 24/7.
You'll find him floating in a pink bubble on the right hand side of your page.
Nothing great is easy. Choose your event, secure your place with a €500 deposit, and take on the iconic distance in warm water.
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