Histria or Istros, was founded as a Greek colony or polis near the mouth of the Danube on the western coast of the Black Sea. It is near the modern town of Istria. It was the first urban settlement on today's Romanian territory when founded by Milesian settlers in the 7th century BC. It was under Roman rule from the 1st to 3rd centuries AD. Invasions during the 7th century AD rendered it indefensible, and the city was abandoned. In antiquity, it also bore the names Istropolis, Istriopolis, and Histriopolis or simply Istros/Histros (Ἴστρος).

Miletus was an ancient Greek city on the western coast of Anatolia, near the mouth of the Maeander River in ancient Ionia. Its ruins are located near the modern village of Balat in Aydın Province, Turkey. Before the Persian rule that started in the 6th century BC, Miletus was considered among the greatest and wealthiest of Greek cities.