Petra

At www.pasthorizonspr.com/index.php/archives/09/2012/land-near-petra-was-a-… …. a system of underground canals cut out of the limestone bedrock took water from reservoirs to terraced fields in the land of the Nabateans, which included Petra. They are well known from the Roman era and the agricultural system appears to have ceased to be kept in order during the early Islamic period – reasons unknown.