The Seine has officially reopened for swimming as Paris basks in a heatwave, turning the city into a water park without the crowded parking lots.

Tourists arrive in matching floaties and snorkels, while locals test whether a baguette can double as a flotation device and still pass as haute cuisine.

City officials framed the move as a temporary experiment in urban resilience, because nothing says summer like a river-sized pool with a byline that reads temporary.

Lifeguards, now the hottest new neighborhood association, spend shifts reminding bathers that sunscreen does not count as a life preserver.

A water quality briefing described the Seine as swim-friendly under supervision, with turbidity rated as fashionably chic and depth depending on your confidence in gravity.

Vendors along the banks have sprouted pop-up stands selling sunscreen, inflatable swans, and croissant-shaped flotation devices.

Local schools plan field trips to study currents, while students discover that science class now includes a mandatory splash tolerance test.

Bridge photographers report record traffic as tourists queue for the perfect river selfie, proving that a splash is a better exit interview than a Louvre visit.

Some residents grumble about algae and slippery stones; the mayor assures its nature confetti and that the river bath will not wash away civic pride.

The tourism board predicts a surge in overnight stays, spiking demand for towels and river chic fashion statements.

In a press conference that felt more like a poolside gala, officials declared climate adaptation a virtue and promised more open water experiments if this one swims.

As the first weekend closes, the Seine keeps its doors (and chaperones) open, ensuring Paris remains the only city where a river is both a landmark and a swimming hole.