This is the beautiful beach called Cala Sabina in Asinara island. Asinara used to be a prison island where mafia criminals spent their inprisonments. The island is now a protected national park and marine biology research centre, visiting is allowed for a limited number of tourists per day, with authorised guides only.
Sardinia is the second-largest island in the Mediterranean Sea (after Sicily). The area of Sardinia is 24,090 square kilometres (9,301 sq mi). The island is surrounded (clockwise from north) by the French island of Corsica, the Italian Peninsula, Tunisia and the Balearic Islands. Sardinia is a constitutional part of Italy, with a special statute of regional autonomy under the Italian Constitution. http://en.wikipedia.org/wiki/Sardinia