He swims down the Doubs

An engineer by training, Iven de Montandon took on the challenge of swimming down the Doubs from its source in Mouthe to Verdun-sur-le-Doubs. But nothing went as planned. Today he recounts his astonishing journey in a book published this Thursday, January 23, 2025 by Éditions Eyrolles.

We dive into his story like a novel. He jumped into the water twice. The first, from September 15 to 28, to go down the Doubs from its source at Mouthe until it flows into the Saône at Verdun-sur-le Doubs. The second, to write this book, “Aventurier en eaux vives”, published this Thursday, January 23, 2025 by Éditions Eyrolles.

He now lives in Isère but was born in Franche-Comté. His family comes from Montandon (Doubs), a small village of 370 inhabitants camped on the Maîche plateau. He also made it his pen name. An engineer by training, he left the region a long time ago but he has never cut ties. And it was on one of them that Iven de Montandon had this somewhat crazy idea. “I was driving on the A36 motorway between Beaune and Dole, I was bored behind the wheel, he remembers. And then, while passing the viaduct which spans the Doubs, I saw the sign with the three small sinusoids which indicate that we are crossing the river. J‘I asked my wife to look on the internet to see how long the Doubs was. She looked at me and said: 453 km.”

Nothing to scare the athlete. Quite the contrary. “I did a quick calculation: two minutes per 100 meters, I have enough for a month.” he smiles today. The man is a competitor and he has a taste for extremes. At 57 years old, he already has an impressive track record behind him. “Finisher” of numerous “Ironman” in Germany, Portugal, Switzerland or Italy, he even competed in the long distance triathlon world championships. “I have always liked to test my limits, to experience my vulnerability and I always choose events in XXL format!” he confides to France 3 Franche-Comté. He didn't yet know what awaited him.

Iven de Montandon had carefully prepared his expedition but nothing happened as he had planned. “As a good engineer, I had modeled everything, on Excel, I had made a pivot table with all the statistics up to integrating the speed of the surface current, he explains. I had my roadmap and planned to execute my script. But everything was shattered!”

He could not imagine having to go around so many natural obstacles, nor overcome so many difficulties. “I left independently with a bag of food, 40 to 45 kilos of equipment in total, and even if the level of the Doubs is relatively low in September-October, I thought I could easily drag all that by swimming on my inflatable packcraft “, recognizes the fifty-year-old. Very quickly, however, he was caught up by the reality on the ground.

I had to walk a lot more than expected, taking paths that run along the cliffs. I understood that I wouldn't make it. My equipment was too heavy. I threw away half of my food right away. I ate every other day, I drank water from the river. I slept where I could.

Iven de Montandon, author “Adventurer in white waters”.

All his plans fall through. Iven de Montandon forgets all his performance goals. He then decides to live this adventure day by day. And open your eyes wide to enjoy the moment and the grandiose spectacle that awaits you all along the river.

Somewhere between the Doubs jump and Goumois, he will even have the nice surprise of seeing his “snow leopard”. A strong nod to the writer Sylvain Tesson, of whom he is a big fan.“A hoarse cry woke me up again well before dawn, he writes. This time, nothing to do with that of the heron.”

A four-legged night hunter was there, right next to the cabin. I recognized him immediately. My heart began to thump. I knew his cry by heart, having listened to it over and over on streaming platforms. A boreal lynx!

Iven de Montandon.

Excerpt from “An adventurer in white water”, Eyrolles editions.

“Wild animals, I have already encountered manyhe explains to France 3 Franche-Comté. I would have liked to come across wolves in Haut-Doubs but it was also a real fantasy to finally see a lynx in real life.”

As the water and the pages flow, we finally see him give meaning to what should initially have been nothing more than a simple sporting exploit. As evidenced by this short exchange with a couple of hikers met on the bank after crossing the Douvot dam, upstream of Besançon. “Why are you doing this?”ask the walkers. “Because I wanted to”replies the adventurer. “I surprised myself saying that.”he confesses. He will finally come out of the water in Besançon, after 324 km of aquatic marathon. There was nothing left for him downstream to explore, he assures.

Because this astonishing journey will have above all allowed him, as he says, to “travel the shores of time” and retrace the course of his life. Like an intimate pilgrimage, a return to the sources. “What I liked the most was the encounter with my childhood memoriesassures Iven de Montandon. It's like all those anecdotes we tell at family meals.”

You find the same clear water flowing over the pebbles, the trees in which you have built cabins, the cry of the buzzards, it's quite profound, to find all your memories in 3D and augmented reality!

Iven de Montandon, author of “Adventurer in white waters”.

This is probably why, even in the worst moments, he never thought of giving up. “I had lots of problems, I got lost, but I never said to myself: I'm throwing in the towel.”. However, he never would have imagined making a book about it. “I thought I'd post photos and videos to Instagram or Facebook every night but my phone started leaking water. I had a little notebook where I wrote down what was happening to me. And it was only afterwards that I was able to make a few posts on social networks. In the comments, some told me: we need to write a book. I sent ten pages to the editor who told me: it’s okay, keep going, we’ll publish you!”

On arrival, 200 pages to read in one go. Happy who, like Iven, has made this beautiful journey on which he takes the reader with complete simplicity. “Ma convictionhe concludes, is that adventure is not always at the end of the world, you can find it at the end of the garden, right behind your house.”