Best Lake Swims in Switzerland for a Summer Day (Free and Near-Free)

Switzerland has more than 1,500 lakes and the water quality of virtually all of them is excellent. Between June and September, lowland lakes warm to 20–24 °C — genuinely comfortable for long swims. The best part: access is free almost everywhere.

This guide covers the highest-value swimming spots, ranked by how easy they are to reach by public transport and how good the water actually is.

Lake Brienz — The Most Surreal Colour

Brienz is the gold standard of Swiss lake swimming. The glacial meltwater carries fine rock particles that scatter light at exactly the right wavelength, producing a turquoise so intense it looks filtered.

• Entry: Free at the public beaches in Brienz village (5 min walk from the train station) and Bönigen (opposite end of the lake)
• Water temp: 18–22 °C in July–August
• Getting there: Direct train from Interlaken Ost every 30 minutes, journey 20 minutes
• Best time: Weekday mornings — the beach fills up on summer weekends

The village of Brienz itself is worth the stop: the wood-carving school and the Rothorn cogwheel steam railway are both within a short walk.

Aare River, Bern — A Capital City Ritual

Floating through the Swiss capital in the turquoise Aare is one of Switzerland's most beloved summer rituals. Every hot day, hundreds of Bernese commuters float from Eichholz or Marzili downstream, climb out at the weir, and repeat. It costs nothing.

• Entry: Free
• Water temp: 16–20 °C in summer (cooler than lakes — it's glacially fed and fast)
• Getting there: Tram 9 from Bern Hauptbahnhof to Marzili (10 min)
• What to bring: A waterproof bag for your clothes and phone — you float downstream, you don't swim back
• Note: The current is fast. Don't swim here if you are not a confident swimmer

If you want a guided introduction to Bern that includes context on the Aare swimming tradition, several walking tours start from the Old Town and end near the river.

Lake Geneva — Urban Beach with Alpine Views

Lake Geneva is Europe's largest alpine lake and the swimming options range from polished to rough-and-ready.

Bains des Pâquis, Geneva: The legendary public bath on the lakefront charges just CHF 2 entry. You get a real beach, a diving board, a sauna, and one of Geneva's best fondue restaurants — on a floating pontoon. The view across to the French Alps and Mont Blanc is exceptional on clear days.

Préverenges and Morges: The north shore between Lausanne and Geneva has long sandy beaches that feel nothing like Switzerland in midsummer. Both are free and easily reached by local train.

• Water temp: 21–24 °C in July–August (the warmest major Swiss lake)
• Getting there: Train from Geneva Cornavin to Morges takes 20 minutes; boat cruises depart from the Jardin Anglais jetty
• Boat option: A classic paddle steamer cruise on Lake Geneva is a worthwhile upgrade for a few hours — the restored Belle Époque vessels still run scheduled routes past Château de Chillon and the Lavaux UNESCO vineyards

Oeschinensee (Kandersteg) — Alpine Drama

This is the alpine lake you see on Swiss calendars: a dark-green tarn ringed by 2,000m limestone walls, entirely free of motor boats, completely silent except for waterfalls.

• Entry: Free (the gondola up costs CHF 32 return)
• Water temp: 12–16 °C — cold, but swimmable for the brave
• Getting there: Train to Kandersteg, then gondola + 20-minute walk
• Season: Mid-June to mid-September (the lake can be frozen until late May)

This is genuinely cold water swimming. Go for the drama, not the warmth.

Caumasee (Flims) — Hidden Forest Lake

Caumasee sits in a limestone forest above Flims, accessible by a small elevator bored into the cliff or a 10-minute walk through the trees. The water is emerald-green and sheltered — it warms faster than exposed glacial lakes.

• Entry: CHF 9 adults, CHF 5 children
• Water temp: 22–24 °C in July–August (the warmest lake in German-speaking Switzerland)
• Getting there: Train to Chur, then PostBus to Flims Waldhaus (total ~1.5 hours from Zurich)
• Facilities: Changing rooms, a small restaurant, SUP and pedalo rental

What to Pack for a Day at a Swiss Lake

• Shoes you can walk in wet: Many public beaches are pebble or grass, not sand
• Sunscreen: Alpine UV intensity is 30–40% higher than at sea level, even when it doesn't feel hot
• A thin layer: The mountains cast shade from 4pm onwards and temperatures drop fast
• Swiss Franc coins or Twint: Some locker systems and smaller snack bars don't accept cards

Practical Notes on Water Safety

Swiss lakes are clean — tested weekly during the swimming season by cantonal health authorities and results published online. The main things to watch:

• Currents: River inflows (especially the Aare in Bern and the Rhine in Lake Constance) create invisible currents. Stay clear of any marked exclusion zones.
• Boat lanes: On larger lakes, marked lanes separate swimmers from boat traffic. Don't cross them.
• Temperature: Alpine lakes above 1,500m stay cold all summer. If you're used to Mediterranean sea temperatures, acclimatise gradually.

When to Go

Lake	Best months	Peak crowd days
Lake Brienz	July–August	Saturday/Sunday 11:00–16:00
Aare Bern	June–September	Any day above 28 °C
Lake Geneva (Bains Pâquis)	June–September	Weekends
Oeschinensee	July–mid-September	School holidays
Caumasee	July–August	Weekends

For the best experience at any of these spots: go on a weekday, arrive before noon, and bring your own food. Swiss lakeside kiosks are excellent but not cheap.

Frequently Asked Questions

Is swimming free in Swiss lakes? Almost always. The Swiss constitution protects public access to natural water bodies. Caumasee and Oeschinensee charge entry (CHF 7–9) because they have managed facilities. Virtually every other lake in this guide is completely free.

Which Swiss lake is warmest for swimming? Lake Geneva and Lake Constance reliably hit 23–25 °C in July–August. Lake Brienz and alpine lakes stay much cooler — beautiful, but cold.

Can you swim in the Aare in Bern? Yes, but it requires reasonable swimming ability. The current runs at 4–6 km/h. The Bernese swim downstream and exit at the Schwellenmätteli or Marzili pools. Don't attempt it after heavy rain when levels are high.

Do Swiss lakes have jellyfish or dangerous wildlife? No jellyfish, no sharks, no dangerous fish. The only thing to watch in summer is occasional blue-green algae (cyanobacteria) in warm, shallow bays — cantonal authorities post warnings when this occurs.

Do I need a Swiss Travel Pass to use the trains to reach these lakes? A Swiss Travel Pass covers most train and PostBus connections to these spots. Otherwise buy a point-to-point Saver Day Pass from SBB.ch (book 7+ days ahead for the best price). Some regional passes (e.g. Berner Oberland Pass) also cover boat routes on Lake Brienz.