Kalhu ziggurat

The ziggurat, which was dedicated to the god Ninurta, was constructed by Ashurnasirpal II (r. 883–859 BC) when he made Kalhu his administrative capital. It is clear from in-situ baked bricks bearing Akkadian inscriptions of his son and successor Shalmaneser III (r. 858–824 BC) that construction on the temple-tower remained unfinished at the time of his death.  Shalmaneser III completed the imposing temple-tower started by his father. The remains of this multi-staged building still tower over the ruins of the once-grand Assyrian capital, which was mistakenly identified as Nineveh in the mid-nineteenth century.

The ziggurat, whose ancient name is not known, had a base measuring approximately 60 x 60 m. The unbaked mudbrick core, which still rises 34 m above the level of the plain, was encased by a six-meter-high ashlar wall and an outer mantel of baked (and inscribed) bricks. Since no completely-intact ziggurat has ever been excavated in Assyria (or Babylonia), it is uncertain what the upper parts of this ziggurat might have looked like or exactly how the upper stages were accessed, although George Smith claims in 1973 to have seen traces of a staircase on the south side of the building. It is now generally thought that the first tier was accessed by an internal staircase within the Ninurta temple, as was the case with other, earlier ziggurats in northern Mesopotamia.

At ground level, a large vaulted room measuring 30 m long, 1.8 m wide and 3.6 m in height was discovered. The exact function of this chamber remains a mystery.