The Histories · 3.152

So when a year and seven months had now passed by, Dareios began to be vexed and his whole army with him, not being able to conquer the Babylonians. And yet Dareios had used against them every kind of device and every possible means, but not even so could he conquer them, though besides other devices he had attempted it by that also with which Cyrus conquered them; but the Babylonians were terribly on their guard and he was not able to conquer them.

Herodotus of Halicarnassus · trans. G. C. Macaulay, 1890
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