Sustainability: Our Impact
If you have swum an UltraSwim33.3 you will know that sustainability is at the core of everything we do. As an open water swimming event, we want to look after our land and oceans as best we can and appreciate the natural beauty of the nature we submerge ourselves in. We believe that as swimmers, endurance events and citizens of the world, we have a duty to protect our planet. This philosophy is one we carry with us in every decision we make, during and outside our events.
We are a carbon net positive event and our impact is a story we would like to keep transparent. We work with a partner called bloomUp who measure our carbon footprint for each event. Being a sports event, we have unavoidable emissions such as flights and speed boats used on the race course. We offset unavoidable emissions with Sea Trees by Sustainable Staff. We are not perfect, but we are actively trying to improve our impact all the time. At our events we try to eliminate single use plastic, we give our swimmers aluminium water bottles and at the feed stations we use re usable cups. We are working with our parters, precision fuel and hydration, to reduce packaging. Our finisher medals are made out of up-cycled wood and old string from paraglider’s who can’t reuse it.
So what can you do? We ask that you return your water bottles if you already have one at home so we can reuse them. Look after packaging from gels while you’re in the water, we are strict on this and have a no tolerance policy on littering. We will hand you your gels open so you don’t have to fumble around in the water and end up with bits of packaging in the ocean, eat your gel then hand the wrapper back to us. Sunscreen is another big one, we ask you to use ocean friendly sunscreen. A lot of sunscreens contain toxins that cause everlasting damage to the reefs by bleaching the coral. Any sunscreen labelled non-nano zinc oxide or non-nano titanium dioxide is a safer option for our reefs. This is especially important for our long distance swimming events in Greece, Montenegro and Croatia where the sun is shining yet the coral below needs looking after and if you are spending hours each day in the water appreciating it, you need to help us look after it.
What It Takes to Swim 33.3km: The Mental Preparation
Mental strength in swimming is a huge aspect to training and is often overlooked, but swimming distances such as these is just as much mental as it is physical. Mindset is essential to endurance swimmers because you spend so much time on your own inside your own head. If you are in control of your thoughts and self-talk, your race strategy becomes a lot easier, especially when you start to get physically tired. Being aware of your mind in the water when swimming long distance is the first step to making a conscious change to your mindset. This is such an important skill to have, there will be times during your swim where you question your why and it’s at times like these where your mental game comes into its own. It’s a good idea to talk to your coach about mental strategies in the water, and we have extensive resources in our swimmer bubble about all aspects of training which will be available to you after you sign up. Once you’ve built mental resilience, it’s time to focus on the experience itself because UltraSwim33.3 isn’t just about the distance; it’s about discovery and adventure.
33.3 kilometres is a long way, but what does it really take to conquer one of the world’s renowned endurance ultra marathon swims? It’s not for everyone but anyone can do it.
UltraSwim33.3 is an ultimate endurance challenge in some of the world’s most beautiful locations. When you can pick a location from the sunny island of Skopelos in Greece to the Balkan fjords of Montenegro, swimming 33.3km suddenly seems less worrying.
Having a supportive team around you is so important and Ultraswim33.3 is unique in the way you make friends because it’s held over 4 days. You have all trained for the same event and you go through something huge together. This sense of community is like nothing else in any other event, simply because you do everything together over the four days of the event. We offer a friends and family program too because we know how much of a difference it can make to be supported by your loved ones. This is called our F3 program, specially designed so you can bring a non-swimming partner with you. They will go out on a boat and support you on your swim.
33.3 kilometres may sound daunting, but with the right mindset, support, and determination, it becomes more than a challenge, it becomes an epic adventure. That’s the UltraSwim33.3 experience.
There is a great theory of Sir Clive Woodward’s (Coach of the England rugby team) which is called the nice nonessentials. These are things which are nice to have and will undoubtedly enhance performance, but you don’t necessarily need them to swim well. UltraSwim33.3 offers a lot of these! From 5* hotels with extensive breakfasts to massage treatments at the end of your swim, we will make sure you have an amazing experience outside of your swim as well as during. We all know how important a good night’s sleep is and there is nothing worse than being stuck in a hotel room the night before an event with a bad pillow!
There is a very experienced team of staff at every event, all of whom have a good understanding of high level sport so you will be well looked after and have a huge disposal of knowledge at your fingertips.
Our Locations
Imagine gliding through turquoise waters off the coast of Skopelos, sunlight flickering beneath you as dolphins swim nearby. UltraSwim33.3 in Greece takes place in the wild island landscapes of white cliffs and green pines, meeting water so clear you can see the ripples of sand on the sea floor. The morning air buzzes with excitement as swimmers gather on the beach, their chatter and nervous laughter mixing with the hum of boats preparing to start their epic adventure swim. This is the real challenge, where swimmers will push themselves through a landscape so beautiful it feels unreal. Each morning, the air feels charged with anticipation with swimmers preparing for the ultimate test of endurance. Aboard the transfer boats, there are stretching groups on the top deck while the captain plays ABBA all the way! So, prepare for a Mamma Mia-themed adventure on the wild island of Skopelos, ditch the wetsuit and pack your flares!
Montenegro was where it all began for UltraSwim33.3. You will swim through the fjords of the black mountains and around and incredible amount of Balkan history. On the day of the marathon swim for our 2025 event, the swimmers started at the monastery which had been built upon its own island. The clouds sat on the top of the mountains and let a stream of sunlight through the church spire. The swimmers hugged the coastline as they swam past some incredible wonders of Montenegro. The first was a shipwreck from the Yugoslav War, a huge steel warship lying on its side on the water's surface. Then onto a submarine pen at about 8km, an abandoned Cold War military facility. What used to be disguised in the face of the mountain is now an open feature in the Bay of Kotor, open for the swimmers to swim into it. Talk about adventure swimming! We had a swimmer with us who worked for NATO and he swam all the way with a NATO flag in his tow float to get a photo inside the pen to show his colleagues. This swim gives the perfect taste for what Montenegro is and is the best way to experience a new country.
Set on the fresh waters of Lake Geneva (Lac Léman), bordered by the Swiss and French Alps, the Switzerland event features the iconic Lausanne–Evian crossing. The freshwater conditions shift buoyancy and work the tides in ways unlike the sea. The route crosses between nations during the stretch from Switzerland into France, offering not just physical demands but an expansive, alpine horizon as your backdrop. Even in the heart of the alps, water temperatures hover around 22-25 °C in the summer. The lake’s calm early mornings sometimes give way to wind-swept afternoons, so open-water swimmers must expect variety but that’s the nature of an alpine swim. Here, your mental game matters just as much as your stroke count: the long swims, fresh water feel, and changeable conditions make it a true test of resilience, showing what endurance open water swimming is all about.
In the coastal waters of Croatia, swimmers take on the 33.3 km challenge amid a breathtaking island-hopping adventure. This event is unique in that it is the only one where swimmers can take on the ultimate format, swimming either 22.2km or 33.3km in one go. This is taking long distance swimming to the next level, offering swimmers a chance to swim the English Channel distance in a stunning Mediterranean location. The course winds through turquoise channels between rocky isles off Hvar, past historical stone forts and through deep-blue Adriatic basins. It’s a swim where the natural beauty of Croatia, with the sun-lit cliffs, crystalline water, and island life, mean you will never get bored of the setting.
Mental Health in Swimming
At UltraSwim33.3, our mission is to be an event that anyone can participate in. We average at around 23 different nationalities per event, all from different swimming backgrounds and abilities. The beautiful thing about UltraSwim33.3 is that it doesn’t matter where you come from, you are all undertaking the same epic test of endurance. “I’ve worked in many sports over the years and without a doubt open water swimming is the most diverse in every sense of the word. Considering age, background, ability, weight, shape size, class - swimming truly is becoming a sport for everyone, and is the one sport we can also keep on doing pretty well until we die, and always in contact with nature! It’s what makes it so special and why it’s growing so fast.” - Mark Turner, Founder.
For the majority of participants, UltraSwim33.3 is a truly life changing event. Not only are you proving to yourself that you are capable of incredible tests of endurance, you are also immersed in a huge sense of community. There is nothing like a four day ultra-marathon swim to bring people together! Swimming has huge benefits to mental heath, you learn to be comfortable in your own mind, alone, something a lot of people go through life without doing. Being in the sea has proven positive effects on our skin and immune system because of the minerals and anti-inflammatory effects of salt water. And, when you swim, you are forced to control your breathing, like a form of meditation. So what do we offer? We hold swimmer talks each evening during the events, these range from inspiring swimmers talking about their experiences to talks about nutrition, strategy and mental preparation. Recently, we have had Jay Prchal with us at our Montenegro swim events. He is an Australian holistic lifestyle coach (ex competitive pool swimmer) who specialises in emotional wellbeing and personal perspective.
Some of you might know Andy Donaldson, Jay is Andy’s mentor and has supported him throughout his Ocean 7’s journey. He has been an amazing advocate for mental health in swimming and at our events he talks freely and openly with our swimmers, helping them overcome the mental challenges of long-distance adventure swimming. He has time for everyone and no query and qualm is too much trouble. As well as team members like Jay, we have an amazing group of volunteers and staff who will support you every step of the way, even if you just need a warm hug at the finish line.