The Hanging Gardens of Babylon
The Babylonian Empire fits between the earlier Assyrian Empire and the later Persian Empire. At its height, King Nebuchadnezzer (sometimes: Nebuchadrezzer) commissioned the Hanging Gardens, circa 560 BC. Built high and behind tall walls (said to be 75 feet tall) finished with decorative glazed bricks, the gardens were served by an intricate irrigation system which required water to be lifted to the highest point in the gardens.
Nothing remains today, except the word "Babylon" which, because the city was legendary for sensual living, is now synonymous with immorality/Hollywood.