AMSTERDAM (AP) — While Parisians have recently rediscovered the pleasure of swimming in the Seine, Amsterdammers have been enjoying a cooling dip in the Dutch capital’s Ij waterway for years.

In a country dominated by waterways, canals, rivers and below-sea-level pastures, wild swimming is on the rise in the Netherlands as climate change increases temperatures and extends the summer season.

Amsterdam had just one official open-water swimming location in 2023. This summer, the city has 13 legal options for taking the plunge in a canal, pond or river, though residents frequently avail themselves of dozens of unofficial spots.

Tucked off of the Ij, a short walk from Amsterdam’s central train station, the Marineterrein, a former base used by the navy since the 1600s, is one of the newest official spots.

On a hot afternoon, the jetties and nearby parks are crammed with locals swimming, sunbathing and relaxing in the shade with a full-size replica of an 18th-century Dutch East India Company cargo ship moored nearby.

“I saw a video on Instagram showing some different places you can go swimming and this was nearby so I was like, ‘perfect, let’s go,’” Noortje Mol, who had just gotten out of the water, told The Associated Press.

In famously egalitarian Amsterdam, there are neither showers nor lifeguards and the area is free for everyone to use. The former base was only designated a legal swimming area earlier this year. Before that, locals risked a 170-euro ($200) fine.

The city tests water quality regularly and the results are published on a national website.

“People think it’s dirty, but it’s not dirty at all,” said Argentinian Mike von Hütter, as he sat on a towel on the jetty.

The early-morning crowd skews older and sportier than the afternoon revelers. A woman on a run stripped off her workout clothing and dove in, swimming a few laps before redressing and continuing her jog.

“Every morning is a light show,” said Myra de Rooy, 68, who started swimming at the naval base during the COVID-19 pandemic.

Many Dutch swimming areas allow skinny dipping and some so-called “naked beaches” even require nudity. While bathing suits are supposed to be worn at the naval base, some among the morning crowd flout the rules.

There is a changing area but, de Rooy explained, in the morning no one uses it.

Despite the expansion of official swimming locations, many locals still jump into the nearest water when they want to cool off.

On the other side of the city, Hans, who declined to give his last name because he was swimming in an unofficial location, does his morning laps in a canal alongside passing boats.

“I swim every day, I’ve never had a problem,” he said.