What were the eastern borders of the roman empire?

"margin-bottom:.0001pt;line-height:normal;">The eastern borders of

the Roman Empire run north-south along the Armenian Highlands (in

present day Eastern Turkey) and the turned westwards along the part

of the Taurus Mountains which is in present day southeaster Turkey.

The former formed the border with the Iran and the latter formed

the border with Mesopotamia (Iraq). Both areas were under the

Persian Empire. The eastern border then run southwards, cutting

through present day Syria, Jordan and north-western Saudi Arabia

and reached the Red Sea. Here the border was with the Arabs.