Some part of the country is encompassed by the Caucasian mountains; for branches of this range advance, as I have said, towards the south. These districts are fruitful, comprise the whole of Iberia, and extend to Armenia and Colchis. In the middle is a plain watered by rivers, the largest of which is the Cyrus, which, rising in Armenia, immediately enters the above-mentioned plain, having received the Aragus,955 which flows at the foot of the Caucasus, and other streams, passes through a narrow channel into Albania. It flows however between this country and Armenia in a large body through plains, which afford excellent pasture. After having received several rivers, and among these the Alazonius,956 Sandobanes, the Rhœtaces, and Chanes, all of which are navigable, it discharges itself into the Caspian Sea. Its former name was Corus.