Roman Cistern
The big underground cistern was built on the east side of the Greater Propylaea, inside the wall, so as to secure sufficiency of water in the main sanctuary.
It consists of two subterranean vaulted spaces which are constructed of stones and kiln-baked mudbricks, coated internally with impervious plaster to achieve absolute damp-proofing. The first space served as settling tank. There took place the purification of water, a first filtration, through the sedimentation of impurities. From the second space, the tap chamber, water was pumped out.
To gain access to this cistern complex a narrow staircase with stone steps had been built.
The upper compartment of the cistern, where the entrance lies, preserves traces of marble panneling that denote the luxuriant character of the structure.
Water management was one of the main priorities in the renovation of the Sanctuary in Roman times. The Roman emperors, constructed large cisterns with the aim to collect an ever increasing quantity of water that was necessary for meeting the needs of the numerous fountains and bath installations.
Emperor Hadrian (117-138 AD), who was himself too initiated into the Eleusian Mysteries, carried out important hydraulic engineering works in Eleusis. These include channeling of the Eleusinian Kephisos riverbed, construction of the visible, until today, bridge at the entrance of the city, as well as the aqueduct of the Thriasian Plain, which carried water of good quality from the springs of Mt Parnitha to supply the city and the Sanctuary. Large sections of Hadrian’s aqueduct are still visible in several places in the city.
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