Alberobello stands on two hillsides, which had been interrupted by a riverbed. On the eastern hill there is the new town with modern architectural features while on the other top line the "trulli", divided into two districts: Monti and Aia Piccola, both National Monuments and from December 1996 recognized by U.N.E.S.C.O. World Heritage.
Trulli are the typical dwellings descended from ancient traditions, but have in common with the homes of primitive peoples only the outer form: a cylinder surmounted by a cone. The trulli are entirely made of stone, no mortar, no timber, no other means of support or connection are used.