After the fall of the Assyrian Empire, a Chaldean named Nabopolassar took the throne of Babylon and, through careful alliances, created the Neo-Babylonian Empire. His son, Nebuchadnezzar II (604-561 BCE), renovated the city so that it covered 900 hectares (2,200 acres) of land and boasted some the most beautiful and impressive structures in all of Mesopotamia. Every ancient writer to make mention of the city of Babylon, outside of those responsible for the stories in the Bible, does so with a tone of awe and reverence. Herodotus, for example, writes:
The city stands on a broad plain, and is an exact square, a hundred and twenty stadia in length each way, so that the entire circuit is four hundred and eighty stadia. While such is its size, in magnificence there is no other city that approaches to it. It is surrounded, in the first place, by a broad and deep moat, full of water, behind which rises a wall fifty royal cubits in width and two hundred in height.
Although it is generally believed that Herodotus greatly exaggerated the dimensions of the city (and may never have actually visited the place himself) his description echoes the admiration of other writers of the time who recorded the magnificence of Babylon, and especially the great walls, as a wonder of the world. It was under Nebuchadnezzar II’s reign that the Hanging Gardens of Babylon are said to have been constructed and the famous Ishtar Gate built. The Hanging gardens are most explicitly described in a passage from Diodorus Siculus (90-30 BCE) in his work Bibliotheca Historica Book II.10:
There was also, because the acropolis, the Hanging Garden, as it is called, which was built, not by Semiramis, but by a later Syrian king to please one of his concubines; for she, they say, being a Persian by race and longing for the meadows of her mountains, asked the king to imitate, through the artifice of a planted garden, the distinctive landscape of Persia. The park extended four plethra on each side, and since the approach to the garden sloped like a hillside and the several parts of the structure rose from one another tier on tier, the appearance of the whole resembled that of a theatre. When the ascending terraces had been built, there had been constructed beneath them galleries which carried the entire weight of the planted garden and rose little by little one above the other along the approach; and the uppermost gallery, which was fifty cubits high, bore the highest surface of the park, which was made level with the circuit wall of the battlements of the city. Furthermore, the walls, which had been constructed at great expense, were twenty-two feet thick, while the passage-way between each two walls was ten feet wide. The roofs of the galleries were covered over with beams of stone sixteen feet long, inclusive of the overlap, and four feet wide. The roof above these beams had first a layer of reeds laid in great quantities of bitumen, over this two courses of baked brick bonded by cement, and as a third layer a covering of lead, to the end that the moisture from the soil might not