This is the Borromeo Palace and Gardens on Isola Bella in Lago Maggiore in the Piedmont region in Italy.
Who can resist to such beauty and elegance?
In 1632, Count Vitaliano Borromeo began the construction of the monumental Baroque palace and the majestic and scenic gardens, which have made the island famous and which to this day bear witness to the splendours of an era.
What is fascinating about this place is an unparalleled "dream setting". I have been to Stresa myself, an elegant and unbelievably picturesque town on the lakeside from which you get absolutely breathtaking views of Isola Bella. You would want to go back.
The Borromeo isles are, besides Isola Bella, Isola dei Pescattori, Isola Madre, Isolino di San Giovanni and Scoglio della Malghera.
Here's some information:
Of the many wondrous sights to see on Isola Bella, one of the most wondrous of all is the shell grotto in the Palazzo Borromeo. The stately palace dominates one side of the island, while its elaborate, ten-tiered baroque-style gardens fill the opposite side. Connecting the two areas is the shell grotto.
Descend a staircase from the main level of the palace into the grotto. The series of six rooms were first conceived in 1685, by Vitaliano the Sixth, with the aid of the architect Filippo Cagnulo. It took 100 years to complete them. In the cavern-like coolness, now as then, the rooms provide a refuge from the summer heat. Every inch of space, including ceilings, floors, and archways, is covered in a mosaic of black and white shells and pebbles. A marble lady is sleeping. Shh…don’t disturb her. She plans to stay dreaming for a long time to come. Down here in the grotto, it’s easy to think you are in a dream. (from Italian notebook)
And if you love the idea of decorating with shells, I recommend you read Theresa's of Art's the Answer blog post called The Shell Game.
images from taccuino di casa bella
image before last from assesempione
text in italics from italian notebook
last image arts the answer