By Jere Mateo
Jeremias Mateo Castillo (43, Spain, MSF bio here, @jereswim, aka Jere Mateo) is a 43-year-old Spanish adventurer, mountain climber, and paraswimmer who got into swimming after a terrible mountain climbing accident.
His ascent in the sport, culminating in his journey towards the Oceans Seven, is steady and gradual. He has done races ranging from the 25 km Batalla de Rande, 10 km Menorca Marathon Swim, and 30.8 km UltraEbre Swim Marathon in his native Spain to the 14.4 km Strait of Gibraltar (3 hours 53 minutes), the 33.5 km English Channel (11 hours 30 minutes), and the 35 km North Channel (12 hours 3 minutes) all in fairly fast times.
He tells his journey…
I’m Jere Mateo: swimmer, father, traveler, and a firm believer that disability is not a limitation, but a different — and powerful — way of facing challenges.
Just a few days ago, I completed the crossing of the North Channel, between Northern Ireland and Scotland, one of the most demanding open water swims in the world. And yes, I did it with chronic pain, with different mobility, and with a community that lifted me when I couldn’t go any further.
In April 2015, a mountaineering accident shook my life.* I lost my friend Salvi and suffered multiple injuries (fracture of six vertebrae with neurological impact on the lower limbs, along with fractures to both femurs, the tibia, the pelvis, and eleven ribs), including a severe traumatic brain injury.
After a month in a coma and a year of rehabilitation, swimming gave me the chance to reconnect with myself and set new goals.
First in the pool, and later in open water, I swim to shift perspectives — to show that disability doesn’t have to be a burden or an insurmountable wall when facing challenges that seem impossible.
That’s how my Oceans Seven challenge was born.
Not just for personal satisfaction, but to prove that yes, even with a disability, we can take on goals that society often sees as extreme.
I’m also defined by how I choose to live. I travel with my family — Olga, Jan, and Guiu — seeking experiences that connect us with people, with history, and with the places we visit.
The North Channel
The North Channel doesn’t forgive: icy waters, stinging jellyfish, unpredictable currents.
I started swimming at 5 a.m., my body tense and mind full of doubt. The first hour, in darkness and waves, was a mental test. Every stroke could mean a jellyfish sting, and not knowing was exhausting.
As the day began to break, I saw the sunrise and felt a slight rise in temperature… but the sun quickly disappeared behind a thick layer of clouds. Typical Irish weather, but far from what I’m used to in the Mediterranean. The next two hours, with constant waves, were tough. Thinking about all the people who support me helped me push through.
And finally, the sun came out…the blessed sun.
It no longer mattered that the water was 14–15°C, or that I kept brushing against jellyfish. I found a steady rhythm. With support from the boat and my challenge partner Bruno, the hours and kilometers passed. Until the final tide change: the sea turned against me and I had to push hard for three more hours.
“It’s all up to you. You’re doing well, but now you need to dig deep,” Bruno told me.
“Give us your two best hours,” said Jack, the Infinity Channel pilot, while Steven kept watch for jellyfish in my path. All under the supervision of Heather, the observer who ensures everything follows the rules. She did her job with steady firmness, but also with incredible kindness and grace.
Stroke by stroke, I reached the beach at Portpatrick. I had visualized it many nights before falling asleep: me, raising my arms on the sand, looking to the sky and thanking Salvi for being with me. And that’s exactly what I did. Without knowing I had finished faster than expected (12 hours 3 minutes), or that reaching the beach was something quite rare. Everything had gone well.
Why I Do It
I swim because I want to live fully. Because I want my children to see that strength isn’t always physical. That vulnerability can be a source of courage. That adapting doesn’t mean giving up — it means reinventing yourself. That my disability and my experience have made me stronger when facing challenges that once seemed unreachable.
I do it for myself, but also for everyone who’s ever felt they don’t fit in. For people with disabilities who want to dream big. And because, borrowing a mountaineering analogy and quoting George Mallory: “Why cross great channels? Because they’re there.”
La Travessia Infinita by Adam Martín is a story that shows how pain can be transformed into energy and how Mateo has overcome a terrible mountain climbing accident in April 2015 in the Alps.
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