A 3000-year-old mysteryThese are constructions of huge stones piled up without any type of cement, which have stood the test of time and still stand out majestically - overlooking the sea, on high mountain summits, on hills and in the plains.Their original function is not yet clear, though hypotheses abound in archaeology books and in the minds of many aficionados, who enthuse about and admire them. In Sardinia, there are 8000 examples, in Dorgali alone around 40.