Cistern
A cistern (Middle English cisterne, from Latin cisterna, from cista, "box", from Greek κίστη kistê, "basket") is a waterproof receptacle for holding liquids, usually water. Cisterns are often built to catch and store rainwater. Cisterns are distinguished from wells by their waterproof linings. Modern cisterns range in capacity from a few litres to thousands of cubic metres, effectively forming covered reservoirs.
Origins
Early domestic and agricultural use
Waterproof lime plaster cisterns in the floors of houses are features of Neolithic village sites of the Levant at, for instance, Ramad and Lebwe, and by the late fourth millennium BC, as at Jawa in northeastern Lebanon, cisterns are essential elements of emerging water management techniques in dry-land farming communities.
Castle cisterns
In the Middle Ages, cisterns were often constructed in hill castles in Europe, especially where wells could not be dug deeply enough. There were two types: the tank cistern and the filter cistern. Such a filter cistern was built at the Riegersburg in Austrian Styria, where a cistern was hewn out of the lava rock. Rain water passed through a sand filter and collected in the cistern. The filter cleaned the rain water and enriched it with minerals.