UltraSwim 33.3 offers you the opportunity to complete the iconic 33.3km distance of the English Channel,
spread over 5-7 swims, over a 4-day long weekend, in an adventure swim point to point race format, in stunning locations around the world.
This is not your average sporting event, swimming 33.3km even over 4 days is a challenge for any swimmer,
and our races take place in varied and challenging conditions that will push you to your mental and physical limits.
We can’t guarantee you’ll become a 33.3 Finisher the first time around, but we can guarantee you won’t regret taking part.
With our flexible rollover policy, better to enter now and reserve your spot even if you are not 100% sure about your availability or event choice.
It’s not for everyone.
But everyone can do it!
Join us at one of these upcoming events…
#6VIRTUAL
The ‘33 days of training’ edition
17 March -18 APRIL, 2025
Swim the iconic 33.3km distance of the English Channel, spread over not just the usual 4, but 33 days! In your local pool, whilst travelling or in open water, divided over as many sessions as you want - just nail a full 33.3km between 17 March and 18 April 2025, including at least one straight 5km swim, and BE ENTERED IN TO THIS AMAZING FREE PRIZE DRAW.
You could win a free entry to #10Montenegro October 2025 (or the 2026 edition) worth 1800 Euros. We’ve also got some our cool UltraSwim 33.3 microtowel ponchos, THEMAGIC5 goggles and Precision nutrition as prizes! All Finishers, regardless of speed or total distance swum beyond 33.3km, will have an equal chance of winning.
Record all your swims from 17 March onwards, EITHER in the new OPENSWIM app OR via your Strava account (join our Strava Club), to be classed as a #6VIRTUAL Finisher and be entered in to the prize draw.
Both the OpenSwim app and Strava apps are free (no need to be Premium member on Strava either). If you don’t use a watch or device to record your swims, you can even add them manually in the OpenSwim app (but not on Strava). OpenSwim is a new app - and for now only available in Europe (inc UK), on Apple and Android.
#7CROATIA
The ‘Islands’ Edition
Welcome to the sunniest island in Europe and the perfect way to start the open water swimming season in the northern hemisphere!
This racecourse takes swimmers between the two beautiful and ancient villages of Stari Grad (start) and Hvar Town (finish) via secret bays and stunning islands. What Croatian waters has to offer both above and below the waterline will blow you away.
The water temperature is expected to be between 18-21°C
16-19 MAY, 2025
Our recommended ULTRA+ package includes:
Entry for the 4-day event
Hotel 4* or 5* for 4 nights (based on double occupancy, single occupancy upgrade available), 3 of them in Stari Grad, and final night in Hvar Town
Dedicated airport transfers from/to Split airport
Pre-event training plans, preparation and support
Personal 1:1 video analysis pre-event
Early breakfasts and post-race refuel lunches
Swimmers pack (dry bag, poncho, water bottle…)
Post swim massages (days 1-3)Preparation webinars and clinics
Optional partner supporter activity package for Family, Friends and Fans (we call it F3)
#8SWITZERLAND
For Leman hope, the ‘Lake” Edition
Lake Geneva (more correctly known as Lac Léman) sits between the Swiss and French Alps, and the Swiss/French Jura - with Geneva at one end and Chillon/Montreux 70km away at the other. This fresh water lake provides an incredible swimming venue, with amazing 360 degree views, and UNESCO heritage vineyards rolling down to quaint Swiss and French villages on the lakeside.
As summer draws to a close, early September can be a stunning time to swim on this lake - the tourist season is winding down, the schools are back, and the lake can show its too faces…mirror like conditions, and end of summer thunderstorms.
5-8 SEPT 2025
In 2025 this event is a Founders’ Pioneer event. SOLD OUT!
As previous participants and invited swimmers only, you are helping us create new events as part of the UltraSwim 33.3 series. These events are pioneering new venues, validating our hotel choices, helping us define the courses and the logistical solutions - in an intimate 20 swimmer max environment much like our very first #1Montenegro in 2022.
SOLD OUT
#9GREECE
The ‘Mamma Mia’ Edition
SOLD OUT!
Welcome to the latest edition to our Epic Adventure Swim Race Series™, hosted on Greece’s greenest island, Skopelos - home also to the cult film Mamma Mia!
This racecourse takes us around the unspoilt wild coastlines, both exposed and sheltered from a regular strong north wind and of course, whether you love it or hate the film, passing the famous filming locations.
The water temperature is expected to be between 22-26°C
19-22 SEPTEMBER, 2025
Our recommended ULTRA+ package includes:
Entry for the 4-day event
Hotel 4* or 5* for 4 nights (based on double occupancy, single occupancy upgrade available)
Dedicated airport transfers, water taxi direct to the Adrina Hotel, Panormos, Skopelos island
Pre-event coaching, preparation and support
Personal 1:1 video analysis pre-event
Breakfast and post-race refuel lunches included
Swimmers pack (dry bag, poncho, water bottle)
Post swim massages (Days 1-3)
Preparation webinars and clinics
Optional partner supporter activity package for Family, Friends and Fans (we call it F3)
#10MONTENEGRO
The ‘Fjords to the Sea’ Edition
Welcome to the original UltraSwim 33.3 Epic Adventure Swim Race™ location - Montenegro.
One of the smaller countries of the Balkans, #10Montenegro’s racecourse offers both wild mountain backdrops and deep fjords, as well as rugged Adriatic coastline, producing a variety of conditions. Highlights include swimming through an abandoned submarine pen and the iconic Blue Cave.
The water temperature is expected to be between 18-22°C
3-6 OCTOBER, 2025
Our recommended ULTRA+ package includes:
Entry for the 4-day event
Hotel 4* or 5* for 4 nights (based on double occupancy, single occupancy upgrade available)
Dedicated airport transfers
Pre-event coaching, preparation and support
Personal 1:1 video analysis pre-event
Breakfast and post-race refuel lunches included
Swimmers pack (dry bag, towel, water bottle…)
Post swim massages (Days 1-3)Preparation webinars and clinics
Optional family package (F3)
