At Shushan — i.e., Susa. At this time (see Records of the Past, vol. 1, p. 71, &c.) Susa was, as Daniel describes it, in the province of Elam; at a later period it became the capital of the Persian empire. Daniel was at Susa only in vision, he was not bodily transported thither. The Ulai is the river Eulæus, and is mentioned in connection with Susa in the inscription cited above.
Related Commentaries of Daniel 8:2
Daniel 8:2
2 And I saw in a vision; and it came to pass, when I saw, that I was at Shushan in the palace, which is in the province of Elam; and I saw in a vision, and I was by the river of Ulai.