Greek descriptions of the Hanging Gardens survive and a relief in the British Museum shows how the hanging gardens were provided with water. The illustrations below show the original and a diagrammatic analysis of the original. With so little known about the layout of such diagrams, it is not possible to produce even a diagrammatic plan. It was probably closer to the Egyptian domestic garden than any known layout.
This relief, now in the British Museum in London, is believed to show the 'Hanging Gardens of Babylon' which are, in fact, most likely to have been in Nineveh. The structure at the top is an arcaded shelter outside the city walls. A stream can been seen running through the gardens. The feature which made the gardens so famous is the mechanism which pumped water up from the River Tigris so that it could irrigate fruit trees and flowers as it triclked back down the hill.
Relief, British Museum