The Trappitello del Duca is an admirable example of an underground oil mill dating back to the 16th century entirely dug into the bedrock, and part of a complex oil-processing system that has been in operation for over four centuries, located just outside the original settlement of Giurdignano.
Visitors can enter the oil mill by a barrel-vaulted staircase that leads into a large hypogeal room. This was where the milling basin was located, as documented by the presence of the still visible millstone there. All around there are rooms used to store olives, called "sciave," storage rooms, and the premises where the "trappetari" could rest and the mule stable.