The works ascribed by Herodotus to a queen, Nitocris, whom he makes the mother of Nabonadius (Labynetus) must be regarded as in reality constructions of that monarch himself, undertaken with the object of protecting Babylon from Cyrus.

They consisted in part of defences within the city, designed apparently to secure it against an enemy who should enter by the river, in part of hydraulic works intended to obstruct the advances of an army by the usual route.

The river had hitherto flowed in its natural bed through the middle of the town.

Nabonadius confined the stream by a brick embankment carried the whole way along both banks, after which he built on the top of the embankment a wall of a considerable height, pierced at intervals by gateways, in which were set gates of bronze.

He likewise made certain cuttings, reservoirs, and sluices at some distance from Babylon towards the north, which were to be hindrances to an enemy's march, though in what way is not very apparent.