I was looking for something like this when I read the headline. Interesting.Later, trade and conquest served as a catalyst for the further expansion of qanat technology both east and west. Roman civil engineers employed qanats in conquered lands where their signature aqueduct technology proved unsuitable. For example, in Jordan, the so-called Gadara Aqueduct, which is a Roman structure unearthed about a decade ago, is not a true aqueduct, but rather a subterranean water tunnel—a qanat—and at 170 kilometers (105 mi), it is the longest such tunnel of antiquity. The Gadara system, also known as qanat firaun or “Pharaoh’s Qanat,” was constructed after a visit by the Roman Emperor Hadrian in about 130 ce, and it partly follows the course of an earlier Hellenistic tunnel. The Roman version appears to have been unfinished, although it was put into service in sections.