Son of Paris Mayor to Swim the Entire Seine

The youngest son of Anne Hidalgo, the mayor of Paris, plans to swim the entire 780km of the Seine. Arthur Germain will start from its source near Dijon and swim to where it empties into the sea near Le Havre. He is the only known person ever to attempt swimming the entire length of the Seine, the second-longest river in France after the Loire.

Germain, 20, is already an experienced long-distance swimmer. In 2018, at the age of 16, he became the youngest French person to swim the 33km-wide English Channel, finishing in a respectable nine hours and 47 minutes. He has been swimming since the age of four.

The route. Photo:


He is planning to cover the distance in 52 days, beginning on June 7, and swimming 15 to 20km each day, in about six hours. He will spend the rest of the time “finding food, water, and showers,” he says.

He calls his swim “independent and without assistance”, but it seems to be only partly so. While swimming, he will pull a kayak weighing around 60kg. In it, he will carry his kit for the seven-and-a-half-week journey. This includes a hammock, a tarp for rain protection at night, and a stove. He will set up bivouacs every night and not use any accommodation along the way.

His kayak will also carry at least some food, although 60kg is not enough to nourish him the entire time — especially not the 9,000 daily calories he says he needs. He will also not be drinking from the polluted Seine.



Germain has said that the cold water will make this swim difficult. “The first 70km will be below 17˚C,” he says. “The average to Le Havre is below 19˚C.”

He is preparing for the Seine’s chilly waters by immersing himself daily in 7˚C water to get his body used to the cold. Training photos show him wearing a wetsuit, although it is unclear whether he will wear it during the swim itself. In January, he also kayaked parts of the route to get an idea of the obstacles and to test his equipment.

Because of the quality of the water in the Seine, a doctor will follow him throughout. They will pay particular attention as he swims through Paris. His mother’s administration has been working toward improving the river water. Multiple swimming events are planned there for the 2024 Olympics, but the water quality is not there yet.



Besides Paris, the fabled river also passes through Rouen, several smaller cities, and 360 municipalities. Germain will pass under 321 bridges and through 28 locks during his swim. He expects the locks to slow him down.

He has also had to convince 14 prefectures to let him swim down the river. This was not an easy task, although he has not gone into details. “I will not explain the administrative mess to obtain the authorizations,” he says.

Although many power plants and industrial sites line the river, “I do not want to demonize the industrialists,” he says. “I want to show that the Seine deserves to be preserved for its richness.”