Matera Cathedral (Cathedral of the Madonna della Bruna and Saint Eustace)

The cathedral towers high above the city - actually visible from everywhere.

The Sassi of Matera
Sassi means "stones" and that means the cave houses that were simply knocked out of the stone. The soft tufa allowed natural cavities to be easily eroded. So you dug whole apartments in the mountain, which were constantly expanded by additions. The excavated stone was used to seal the opening of the caves. These dwellings knocked out of the tuff rock were extended in the course of the time also by preceding extensions. The caves themselves were partially expanded to heavily branched complexes of underground premises.
Nested over and over one another over the millennia, a cave city in the rock was created, a network of cave houses, a labyrinth of narrow streets and small squares.

Matera Cathedral was completed in 1270 on the highest and most visible point in the city.