There he appears to have died in B.C.668, or early in B.C.667, leaving Asshur-bani-pal sole sovereign of the entire empire.
Of the architecture of Esar-haddon, and of the state of the arts generally in his time, it is difficult to speak positively.

Though he appears to have been one of the most indefatigable constructors of great works that Assyria produced, having erected during the short period over which his reign extended no fewer than four palaces and above thirty temples, yet it happens unfortunately that we are not as yet in a condition to pronounce a decisive judgment either on the plan of his buildings or on the merits of their ornamentation of his three great palaces, which were situated at Babylon, Calah, and Nineveh, one only--that at Calah or Nimrud has been to any large extent explored.
Even in this case the exploration was far from complete, and the ground plan of his palace is still very defective.

But this is not the worst.
The palace itself had never been finished; its ornamentation had scarcely been begun; and the little of this that was original had been so damaged by a furious conflagration, that it perished almost at the moment of discovery.

We are thus reduced to judge of the sculptures of Esar-haddon by the reports of those who saw them ere they fell to pieces, and by one or two drawings, while we have to form our conception of his buildings from a half-explored fragment of a half-finished palace, which was moreover destroyed by fire before completion.
The palace of Esar-haddon at Calah was built at the south-western corner of the Nimrud mound, abutting towards the west on the Tigris, and towards the south on the valley formed by the Shor-Derreh torrent.

It faced northwards, and was entered on this side from the open space of the platform, through a portal guarded by two winged bulls of the ordinary character.