Ensuring a water supply was a constant concern in ancient times, which was resolved at El Molón by building a series of cisterns carved out of the limestone rock, as well as a cave-spa at the foot of the south-west slope, and the lakes near to Camporrobles, which dried up in more recent times. El Molón has two cisterns in different parts of the site, and a third next to the main entrance, outside the perimeter wall, making it an unusual feature. The recurring presence of cisterns confirms that this was a fairly stable settlement, which is certainly backed up by its spectacular defences and its sheer size.
The big water-storage cistern on the east plateau (Sector C), which is the only one found fully silted, is oval in shape, with straight sides and rounded corners, measuring 7.4 x 7.2 m and with an average depth of 2.5 m, reaching 3 m in the south area, which means it would have had a capacity of around 200,000 litres of water. To the north was a stone wall, which was surrounded by a cut-off pit filled with clay, and with a wall running round the rest of the perimeter, the remains of which were discovered among the abandoned levels. This stone structure has two very different parts. On the north side, the rock naturally undulates to form gentle terracing that was then worked on to create feed channels. Stone blocks were also extracted from here. The south side is deeper and completely vertical, with a rock base covered by a layer of yellowish clay, which may have been to seal the bottom. The structure was probably related to the major restructure that took place around the 4th century BC, and remained in use right up to the settlement’s final period, in the 1st century BC.
Another cistern stands near the main gate into the site, next to the path. Rectangular in shape, it measures 6 x 3 m and is around 2.5 m deep, reaching more than 3 m deep at the south end. It was only partly filled when discovered, and may therefore have been in use during the Islamic occupation of the hill (unlike the previous cistern, which housed constructions from this period), though it undoubtedly dates from the pre-Roman era, as the path leading to the site, which is brusquely cut off by the albacar wall that covers it, and where tracks left by carts can be seen, runs parallel to it.
The most spectacular cistern is known as “El Pozo de los Moros” or Moors’ Well, and is next to the path leading up to the site, outside the perimeter walls, on the west side of the hill. It seems to have been carved out of a natural cavity, as on the uppermost part there is very little evidence of it having been modified, something that can be seen only a few metres further down. Square in shape, it measures 3 x 3 m at the base, whereas on the surface it measures from 4 m (N-S) to 5 x 2.5 m (E-W), given its trapezium shape. It is more than 20 m deep, though the very bottom has not yet been reached, but the way it has been formed and its size (which is similar to others found elsewhere) strongly suggest that it formed part of the site itself.