This time Francesca leads us to a place of which she says:
"visiting the complex of Sant’Andrea Priu you feel that you are entering an archaic sacred place created by man and nature, where the flow of time fixed unchanged the charm of the pagan magic together with the Christian spirituality".

Some notes:
The hypogeum of Sant’Andrea Priu is in the fertile plain of Santa Lucia and is one of the most important complexes in Sardinia.
Dated about 3500-2900 BC, some graves were used and modified up to the Middle Age.
The complex consists of about 20 underground tombs built as the Domus de janas.
Among these there is the "Tomb of the Chief" one of the most spectacular Domus thus far unearthed; it was partially altered in Roman age, and then transformed by the Byzantines in a rock-church reconsecrated in 1313 and dedicated to Sant’Andrea.
The early Christian frescoes and the medieval inscriptions were discovered during the 1969 restoration.
The "Circular hut tomb" and the "Chamber tomb" are remarkable for the awesomeness and the perfect preservation.
The complex of the domus de janas is towered by a particular rock called the "bell tower" or the "sacred bull" partially modelled by the atmospheric phenomena.

For more info:
wikipedia: Necropoli_di_Sant'Andrea_Priu

Thank to our friend Francesca for the beautiful photographs