The Hanging Gardens of Babylon are the most mysterious of the Seven Wonders—so much so that some historians question whether they truly existed. Traditionally attributed to King Nebuchadnezzar II (circa 605-562 BCE), they were supposedly built to comfort his homesick wife, Amytis of Media, who longed for the green mountains of her homeland.
Descriptions from ancient writers like Strabo and Diodorus Siculus depict a spectacular series of ascending, terraced gardens with exotic plants and flowers. An engineering marvel, they would have required an advanced irrigation system to water plants at height in arid Mesopotamia, possibly using an Archimedes screw or chain pump system.
Despite extensive archaeological excavations at Babylon, no definitive physical evidence of the gardens has been found. Some scholars suggest they may have actually been in Nineveh, built by Assyrian King Sennacherib, or perhaps were an idealized literary creation that captured the imagination of Greek travelers.