‘And I saw in the vision, - now it was so that when I was seeing I was in Shushan the fortress, which is in the province of Elam - and I saw in the vision, and I was by the River Ulai.'
Daniel repeats that he saw things in vision, and informs us of his whereabouts at the time. He was in Shushan (Susa), the fortress-city, in the province of Elam. It is quite probable that he was there on a mission on behalf of Babylon, as a retired governor of Babylon now available for such special missions. This would explain why, as he saw the power of Medo-Persia, he recognised that the downfall of Babylon must come soon. On the other hand some see this as meaning that he was, as it were, transported there in the vision.
Shushan was Cyrus' capital city, capital of the Persian empire, a huge fortress of a city in the former territory of Elam, ‘in the province of Elam'. In Ezra 4:9 the ‘Shushancites' are differentiated from the Elamites. This was a differentiation of cityfolk from the provincials. Compare Jerusalem and Judah, often seen in apposition. At this time Elam was a province of either Media or Persia.
The ‘River' Ulai flowed by Susa and was a canal, 275 metres (900 feet) wide, which joined two large rivers.