Switzerland Lago di Poschiavo

Lake Poschiavo is a lake in the Poschiavo valley, Switzerland.
The lake was formed following the post-mortem slope of Mount Giümelin. Since 1904 the lake is exploited for the production of electricity.

If you have never been in that area, I definitely suggest you to go there by the Bernina Express, a train connecting Sankt Moritz, Chur or Davos in Switzerland to Tirano in Italy by crossing the Swiss Engadin Alps. For most of its journey, the train also runs along the World Heritage Site known as the Rhaetian Railway in the Albula/Bernina Landscapes.
Simply amazing.

You can get there by car, bus, train and walk. On the banks of the lake are the villages of Le Prese and Miralago; the towns of Poschiavo and Brusio are 5 and 3 kilometers respectively from the shores of the lake.