Now as one sails into the Euxine Sea from the Propontis, one has on his left the parts which adjoin Byzantium (these belong to the Thracians, and are called "the Left-hand Parts" of the Pontus), and on his right the parts which adjoin Chalcedon. The first of these latter belong to the Bithynians, the next to the Mariandyni (by some also called Caucones), the next to the Paphlygonians as far as the Halys River, and the next to the Pontic Cappadocians and to the people next in order after them as far as Colchis. All these are called the Right-hand Parts of the Pontus. Now Eupator reigned over the whole of this seacoast, beginning at Colchis and extending as far as Heracleia, but the parts farther on, extending as far as the mouth of the Pontus and Chalcedon, remained under the rule of the king of Bithynia. But when the kings had been overthrown, the Romans preserved the same boundaries, so that Heracleia was added to Pontus and the parts farther on went to the Bithynians.