Previously called the Lago di San Giulio, after Saint Julius (4th century), Lago d'Orta is a lake in northern Italy. Located around the lake is Orta San Giulio, a town and comune (municipality) in the Province of Novara.
San Giulio, pictured in this Instagram snap, is characterised by its classic, picturesque buildings and the gorgeous mountain in its backdrop. It is said that residents of the area and its surrounds have kept relatively mum about its breathtaking beauty in an attempt to avoid tourists flocking to the region. It's been working thus far as the area isn't as packed with tourists as other popular Italian lakes.
In a review for The Guardian, Edward Docx wrote: "...for me, what sets Orta apart is not its beauty – though the place is absurdly pretty – but the lake's mysterious, ethereal, almost supernatural quality. There is something for the soul there as well as for the eye."
Judging from this image alone, I concur with Mr. Docx.