Pyrgos appears for the first time in a written source of the Frank era, in a letter of 1224 by Pope Honorius III. The establishment of a monastery in Pyrgos during the same century (13^th) is also mentioned, being the only monastery for men of the Latin (Roman Catholic) Monastic Order of the Cistercians in Cyprus.  It seems that the Cistercian monks resided in Pyrgos from 1238 until 1251, maintaining their properties there at least until the end of the 15^th century. 

The Cistercians cultivated their estate and utilised the agricultural production.  For that purpose they had constructed a high-tech irrigation system, as they were in the habit of doing in their abbeys and other places

The village's extant, imposing, water-driven mill with its characteristic Mediaeval arch in the area of the vane, the triangular cistern above, and the extremely large (35X25 m.), rectangular, double cistern about 300 meters north-west of the mill, are connected with the exploitation of the water's energy.

The cistern was supplied by the waters of a spring that still exists today.  Through a long raceway the water was gathered in the triangular cistern and was channelled to the mill's pit, inside the tall, scaled water-tower.

These constructions, as well as the large-scale irrigation and hydraulic system, are characteristics of the Cistercians' high-tech and unique samples of their type in Cyprus, perhaps also of the entire eastern Mediterranean. 

Because of its architectural and historical importance, the Mediaeval Water-mill in Pyrgos has been declared -since 1984 -as an "Ancient Monument" (Index II) by the Antiquities Department. 

The excavations in the water-driven flourmill -in the village Pyrgos of the Limassol district -are complete.  The excavation focused on three sectors and the following operations were done:

1. In the area of the grinding mechanism, which was covered by landfills (sized 7X8 meters), the following were uncovered: the floor, which is made of stones from the river, the lower millstone, embedded in the ground, and a continuous, trapezoid, basin made of hard limestone, internally covered with lime mortar, which was used as flour vessel.  The second millstone was found lifted by an iron derrick (lift).  Pieces of older millstones, made of volcanic rock from Melos, had been used as material for the making of the floor.
   Cleaning of the floor in the ground-level, arch-covered area of the vane, which is not extant, was also done.
2. In the triangular cistern above the scaled water-tower, standing at a height of about 7 meters above the millstone's level, the floor -covered with plaster and with a substratum of stones -was revealed and the walls were cleaned, as well as the raceway that crosses this cistern, ending in the conveyor of the water-tower.
3. In the region of the rectangular cisterns, which are far away from the water-mill, the floor -made of mortar from the western cistern -was revealed in an area of 8X4 meters. 

At a higher level, north of the western cistern, the more recent, stone-made, raceway (width 30-35 cm) was cleaned.  A section of it was also traced further north and an older raceway (width 1.25-1.50 m), bearing a coating and lime-mortar, was uncovered.  According to the architectural remains, the mill had at least two construction phases and was in use for several centuries, as it is indicated by the very few shells of enamelled pottery that were found in the soils of the floor.