Switzerland
Lucerne is only 45 minutes (with the railway) from Zurich. There is the beautiful Lake Lucerne, which has mountains around it and a famous old town. It is not so overcrowded as Zurich and much more relaxed. You can swim in the lake either in the lido (for a fee) or the equally beautiful "Ufschütti" (for free). The "Ufschütti" is near the railway station (ask for the way, many people in Lucerne speak English). You can also make boat trips on the lake, climb one of the many mountains around the lake or visit the old town.
With the train from Zurich Mainstation to Lucerne (every 30 minutes a train). www.luzern.com/en/
Google map: bit.ly/qqiXmg
The best way to spend a hot day in Zurich is lake or river swimming. The state website lists the daily water temperatures and facilities available at each Seebad or Flussbad, and by night many turn into relaxed bars.
www.stadt-zuerich.ch/content/ssd/de/index/sport/schwimmen.html
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