From the medieval Church of San Nicola passed the ancient Regia Trazzera dei Mulini (still largely existing today), which led to Naro, at the entrance of the Porta d’Oro or Porta Vecchia, the only one remaining of the six gates that once allowed access to the city in medieval times. In the 1830 map of Delia, three water mills are marked south of the Castellaccio. In 1596, two mills already existed, the Soprano and the Sottano, at least one of which is documented as early as 1399. In the early 1620s, two more were added: the Tigaro and the Drogo. A fifth mill stood in the Cottonera district, outside Delia’s territory, built to serve the needs of the large Gibbesi estate, which had been acquired in the meantime and annexed to the Marquisate of Delia. Special mention should be made of the aqueduct that brought water to the first of the three mills, deliberately aligned in series to exploit the same water flow.
These factories operated thanks to a clever system of canals and sluice gates that diverted part of the river’s water towards the mill. Bearing witness to this ingenuity is a truncated-pyramid-shaped pillar, the last remnant of the aqueduct bridge that carried water from one bank of the Delia river to the other. Of the three mills in Delia’s territory, the Sottano still preserves the walls of the entire structure, which could one day allow for its complete restoration. The mills ground durum wheat and broad beans for the ovens and kitchens of the estate, but also produced bran for animals, thus integrating the agro-pastoral system based on almond trees, olive trees, and cereals. Activity continued until the early decades of the 20th century, when competition from modern electric plants and the reduced flow of the Paradiso stream led to their abandonment. Since then, the structures, now covered with mastic bushes and capers, have become a refuge for owls and Sicilian lizards. A short walk starting from the staircase of the “Castiddazzu” leads to the archeo-industrial area of the water mill remains.