After setting off from Corsica on Monday, August 11, Noam Yaron, a 28-year-old Swiss swimmer, left the water on Friday, August 15 after nearly five days and four nights of continuous swimming. An unprecedented feat aimed at raising awareness about the protection of the Mediterranean Sea.
Early on Monday, August 11, 2025, the port of Calvi came alive around an extraordinary departure. Noam Yaron entered the Mediterranean with a clear objective: to swim non-stop from Calvi to Monaco, covering a distance of 180 kilometres. For nearly five days, he moved forward stroke by stroke, day and night, in a physical and mental challenge designed to draw attention to the state of the sea and the urgent need to protect its biodiversity.
This project had been in preparation for two years. In 2024, Yaron had already attempted the crossing but was forced to stop after 100 kilometres due to harsh weather conditions. This time, he returned with greater experience and a scientific monitoring programme, collecting data throughout the journey in collaboration with the Scientific Council of the Lérins Islands (CSIL) and the STARESO research station in Calvi.
A Precise Rhythm and Constantly Changing Conditions
From the very first hours, Noam Yaron adopted a meticulously structured routine: every thirty minutes, an active back-floating pause to hydrate; every hour, a longer break to eat — typically potatoes, bananas, eggs and cinnamon. Food was delivered via a buoy, allowing him to remain almost entirely self-sufficient.
Swimming behind a catamaran that provided navigation guidance, Yaron faced weather that alternated between calm spells and rougher passages. On Monday evening, winds rose to 12 knots, generating waves that occasionally required slight course adjustments. During the nights, unexpected incidents complicated the effort, including a rope becoming tangled in a support boat’s propeller — an issue quickly resolved by the crew.
Marine Encounters and Scientific Monitoring
The days at sea were marked by remarkable encounters. At sunset, jellyfish forced Yaron to wear gloves, booties and a hood. The following night, he swam alongside a playful young dolphin, nicknamed “Baby Flipper.”
In the wake of the support catamarans, scientists collected plankton samples, filtered microplastics and gathered environmental DNA. Observations included sightings of a mobula ray, a fin whale, and a pod of striped dolphins (Stenella).
These data will contribute to assessing the state of the pelagic ecosystem in a sea that, despite its protected status within the Pelagos Sanctuary, remains exposed to pollution, ship strikes and industrial fishing.
Personal Records and the Battle Against Fatigue
By Wednesday morning, after more than 50 hours of swimming, Noam Yaron passed the 110-kilometre mark, surpassing his personal best and exceeding the distance he had reached in 2024. But exhaustion was already setting in. Hallucinations began to appear — sensations of being trapped in a ravine, visions of imaginary animals, or even a fictitious race unfolding in front of Calvi.
To limit disorientation, the team replaced the floating illuminated guide line with a weighted line fixed to the seabed, providing a more stable visual reference. Encouraging video messages from family and friends helped restore his energy. With his consent, an energy therapist also intervened remotely to ease pain and itching caused by prolonged exposure to saltwater.
The Final Stretch
On Wednesday evening, Yaron entered the Ligurian current, an unpredictable zone where weather models often diverge. His morale fluctuated between determination and moments of doubt. Breaks were occasionally extended to allow for short naps.
By Thursday, August 14, only 20 kilometres remained. The team prepared for a forecast storm with gusts expected to reach 50 km/h. While the storm ultimately moved away, strong headwinds slowed Yaron’s progress. His arrival, initially expected around 1 a.m., was delayed — marking the beginning of a mentally taxing final phase.
Pushing to the Limit
Throughout the day, supporters and onlookers waited for the Swiss swimmer’s arrival. The final kilometres proved the most demanding. Battling extreme fatigue and disorientation, Yaron pushed on while the support team remained on maximum alert, ready to stop the crossing if medical concerns arose.
Finally, at around 4 p.m., after nearly five days and four nights without leaving the water, Noam Yaron was forced to end his extraordinary challenge approximately two kilometres from the beach of the Le Méridien Beach Plaza Hotel in Monaco. After moments of concern, his team reassured observers: he was breathing, speaking and was immediately taken into medical care. A press conference is scheduled for the following day to provide further updates.
A Message for the Mediterranean
This crossing was never just a sporting challenge. It carried a clear message: although the Mediterranean represents only 0.8% of the world’s ocean surface, it accounts for 25% of global maritime traffic. Ship strikes are the leading cause of non-natural death for cetaceans. Reducing vessel speed to 10 knots could save countless lives.
During a period of marine heatwaves, with surface water temperatures approaching 30°C as measured by the scientific team, the sea is experiencing alarming overheating. The ocean, a vital climate regulator, is struggling to absorb this excess heat — directly threatening biodiversity and ecological balance.
For Noam Yaron, these five days in the water serve as a powerful reminder of the urgency to act. His 180-kilometre swim stands as a symbol of total commitment — to defending nature and sounding the alarm about a unique yet fragile ecosystem.
Correction: In a previous update, we incorrectly stated that Noam Yaron had broken a world record. This was inaccurate. The swimmer surpassed his own personal record, a powerful symbol of the personal endurance and determination he demonstrated during this challenge.
