This is Alberobella, one of the quaintest spots in Italy, renowned for its unusual Trullo buildings.
More pictures can be seen here.
Typical construction of a trulli in Alberobello. The cavity between the inside wall face and the exterior covering of stone tiles is filled with stone rubble. The vault is one of stone voussoirs (a wedge-shaped or tapered stone used to construct an arch). We had lunch inside one of these buildings. It was quite cosy and definitely one of the most unusual buildings I have ever been in.