The Lej da Staz is super nice in any season. It is only a 20 minutes walk from St.Moritz train station and also just about a 45 minutes walk from Pontresina (Distance: 6.8km Duration: 1:50hrs; Ascent / Descent: 125m).
This lake has become Instafamous by now and in the mornings (especially on weekends and in the golden season -> when all the larches turn golden.) it is usallly busy with photographers. But as you can see from the photos, it makes it's reputation justice :)
Photography tips: I recommend you to shoot for sunrise since you get the best colors. If you are not so much into that, make sure to at least arrive before 11AM because about that is the time when the "Maloja" (as they call the wind) starts to rise and all the reflection is gone.
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