The Akkadian Empire (2334-2154 BCE), carved out in blood by the army of Sargon the Great, put the lion's share of Mesopotamia under the control of a single ruler. It doesn't come up in popular culture really often, but Akkad's cultural and historical significance is huge:
So you'd think, given the empire's importance, that we would have some idea of where the ruins of the imperial capital, Akkad, generally regarded as one of the largest cities in the ancient world, are. And you'd be wrong. We have no idea.
You'll notice two locations on the map above labeled "Akkad": "AKKAD," which was the empire itself, and "Akkad?," which was its mysterious capital. And the question mark indicates, quite accurately, that archaeologists haven't found it yet.
There are several theories as to where it might be. A strong aerial analysis of the region in 1985 seemed to indicate that it was most likely to exist at the Ishan Mizyad dig site, but that's not plausible; the ruins at Ishan Mizyad aren't really big enough, and in any case tablets translated in the late 1990s date it to the reign of the post-Akkadian ruler Ur-Nammu.
Wherever Akkad is, it is clearly in Iraq—and as we know, the situation in Iraq is tragic and unsettling and has been for some time. Critical archaeologist Yannis Hamilakis has correctly chided some elements of the international archaeological community for rather ghoulishly focusing on the survival of ancient historic sites and relics in the face of seven-figure human casualties, but it remains the case that many of these sites are being destroyed and much of what can be found in them will never be replaced or studied further. The fact that Akkad has not been found indicates that one of the greatest finds in the ancient Mesopotamian world—perhaps the single greatest find—is as securely protected from bombs as it is from archaeologists, and will be ready for the world when the world is ready for it.