Which preposition to use with carchemish

on Occurrences 1%

HITTITES, one of the original tribes of Canaan, and one of the most powerful, whose dominion extended at one time as far as the border of Egypt on the one hand, and Mesopotamia on the other, and northward beyond the Taurus Mountains, traces of which have been discovered over all Asia Minor, while they were strong enough to engage in war with the Egyptians; they had two capitals, Kadesh on the Orontes, and Carchemish on the Euphrates.

Which preposition to use with  carchemish