Blausee is a small lake in Kander valley and it is probably the most photogenic lake in Switzerland. Its a nice place to spend the morning and you can have lunch in the restaurant just next to it.
Go check it out if you’re in the area but I wouldn’t travel too far to see it. If you like these blue water and you’re in the mood for some trip further away there is only one place you wanna go: https://madeinbeijing.wordpress.com/2011/11/21/sichuan-jiuzhaigou/