Various ideas

[Meyrie]

Here are some other ideas of what you can do outside:
- rent a pedalo and chill out on the lake
- same with a small boat
- play mini-golf
- visit the Chillon Castle near Montreux
- do some bird-watching/hang around in the nature reserves (ex.http://www.pronatura.ch/decouvrir-des-reserves-naturelles) 
- visit nearby cities (many famous town are easy to access from Lausanne, such as Montreux, Geneva, Vevey, Gruyère etc.)
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