Bathing, barbecues and buvettes are part of the culture in a city that promotes swimming in its majestic river – and it’s a chance for some great sightseeing, too

If you want to join the many swimmers who leap into the Rhine each summer you can’t do the British wade-in – arms in the air, considering whether the water is for you. You have to commit. You have to give yourself to the river and let it be your guide.

I tested out my technique – and bravado – when I visited Basel during Europe’s recent heatwave, when temperatures in the city reached 38C. Fortunately for me, the Swiss have led the way in city swimming: for decades, cities such as Basel, Berne, Zurich and Geneva have been making rivers accessible and safe for swimmers. Developments in the 1980s included building sewage treatment facilities and diverting domestic wastewater away from the river, and concrete steps were built for easier access to the water, and guidelines and maps published for swimmers.

Facebook Twitter Pinterest Swimmers in the Rhine. Photograph: Ella Foote

The Rhine sweeps through the medieval city and is an important trading route. Large flat-bottomed barges share the water with swimmers. Despite the shipping monsters and urban riverbanks, the water isn’t rife with litter or pollution. In fact, it reminded me of moonstone, a pearlescent blend of blues and greens, surprisingly clear. It is fast-flowing and constantly swirling, eddies forming around bridge pillars.

I entered the water from the popular swimming beach of Einstieg Rhyschwimme at the foot of art-packed Museum Tinguely. Most people swim between the Schwarzwald and Johanniter bridges and let the current take them downstream. A sign displays a swimmer’s map, developed in 1984, marking the safe swimming area. There is a makeshift changing room and a couple of toilets, but that’s it. No lifeguards. Swimmers enter the water at their own risk.

Facebook Twitter Pinterest Rheinbad Breite bathing house. Photograph: Armin Smailovic

I put all my belongings, including my purse, phone and passport, into a Wickelfisch. These brightly coloured fish-shaped bags, sold all over the city keep clothes and possessions dry for the duration of a trip down the Rhine. I watched other swimmers entering the water: office workers folded suits and loaded Wickelfisch confidently with laptops; tourists fumbled and followed, as did I.

The fast flow swept me downstream. This isn’t for nervous swimmers: you are immediately out of your depth as you enter the strong stream and water aids are prohibited. I’m an experienced swimmer and the current still unnerved me: my instinct was to swim, kick and control, but relaxing into the flow was the best way.

Facebook Twitter Pinterest Swimmers carrying their possessions in a Wickelfisch bag. Photograph: Markus Buehler

There is plenty of room, with large red buoys marking the swimming area off from that used by boats. The adventure is just over 2km of downstream floating and I had a stupid grin on my face the whole way. Floating down a fast-flowing city centre river goes against all the “rules” we like to outline to swimmers in the UK: like knowing your exit point, and urban areas being often unclean, unsafe. But this was the perfect way to see the sights.

I passed the first of four historic ferry boats that take passengers across the river powered solely by the current. Basel is famous for its blend of historic buildings, such as the Basler Münster (cathedral) and contemporary museums, apartments and commercial buildings. From the water you get a great view of how the city has developed. I swooshed through the arches of Mittlere Brücke, built in 1226 and in no time at all found myself in the midst of the city, looking at riverbanks draped with sunbathers.

Concrete steps at the water’s edge offered swimmers a number of exit opportunities. I set my eyes on orange and green parasols surrounding a popular buvette – an outdoor bar that only operates in summer months. Exiting the water was almost as unsettling as getting in, though. I narrowly missed a string of wooden boats before planting my feet. The whole trip took about 30 minutes and all I wanted to do after was walk back upstream and do it all over again.

Facebook Twitter Pinterest Ferry across the Rhine, powered by the river’s current. Photograph: Ella Foote

Later in the week I joined Selina Speck from the SLRG (Swiss Life Saving Society) for another dip in the Rhine. Selina told me it is rare that people get in trouble, and if they do it is often because they misjudge their own swimming ability. We took the same route together, only this time we walked back upstream afterwards, drank iced tea from buvettes and ate ice-cream on the warm slabs of concrete that dried our bodies before we plunged back in.

Selina explained that the current is usually faster and water level higher than in this hot summer week, so what I had experienced was tame. I spent the afternoon with Selina both of us just in swimwear, not thinking twice about the fact we were walking around the city clad like this. Along the embankment on the Kleinbasel side of the river there are plenty of places to get into and out of the water.

Swimming in the Rhine feels like you are in the soul of the city but Basel has plenty else on offer. Its history is fascinating and I found myself walking the same steps with new eyes after an hour’s walking tour with a guide uncovering secrets of the city. I discovered that bathing in Basel isn’t just reserved for the Rhine; more than 200 historic fountains across the city are also popular for cooling off in.

Facebook Twitter Pinterest Relaxing by the river after a swim. Photograph: Schaffner and Conzelmann

The Swim City exhibition at the Swiss Architecture Museum until 29 September is a celebration of bathing culture in cities across the world and a look at how swimming in cities could look in the future. Exhibits include the Thames Bath: a floating river pool on the river in central London and +POOL – a development that would allow New Yorkers to swim in the Hudson River.

If the sweeping river current isn’t for you, river culture can be soaked up in one of two bathing houses that sit on stilts on the riverbank. Constructed in 1898, the large metal-and-wooden structures offer sunloungers, parasols, changing facilities, and steps down to less-lively water under the stilts for around £5 a day. The Rheinbad Breite bathing house sits opposite the swimmers’ beach on the south bank. Sitting in its restaurant, Le Rhine Blue, I loved watching swimmers sweep past beneath the wooden slats at my feet while I ate antipasti and sea bream.

I’ve always associated Switzerland with winter travel or suits on business trips but as soon as the temperature allows, Basel is all about bathing, barbecues and buvettes. In this city centre a swimsuit is the typical summer outfit.

• Travel was provided by Switzerland Tourism and Basel Tourism. The Swiss Travel Pass (swisstravelsystem.co.uk) also includes the Swiss museum pass, allowing you free entrance to 500 museums and exhibitions. Prices from £185 in second class.

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