One passed along the foot of the Sinjar range by Sidikan (_Arban_) on the Khabour to Tiphsach (or Thapsacus) on the Euphrates, where it crossed the Great River.

Thence it bent southwards, and, passing through Tadmor, was directed upon Phoenicia most likely by way of Damascus.

Another took a more northern line by the Mons Masius to Harran and Seruj, crossing the Euphrates at Bir, and thence communicating both with Upper Syria and with Asia Minor.

The former of these two routes is marked as a line of traffic by the foreign objects discovered in such abundance at Arban, by the name Tiphsach, which means "passage," and by the admitted object of Solomon in building Tadmor.

The other rests on less direct evidence; but there are indications of it in the trade of Harran with Tyre which is mentioned by Ezekiel, and in the Assyrian remains near Seruj, which is on the route from Harran to the Bir fordway.
Towards the north, probably, the route most used was that which is thought by many to be the line followed by Xenophon, first up the valley of the Tigris to Til or Tilleh, and then along the Bitlis Chai to the lake of Van and the adjacent country.