Histria or Istros was founded as a Greek colony or polis on the western coast of the Black Sea near the mouth of the Danube whose banks are today about 70 km away. In antiquity, it also bore the names Istropolis, Istriopolis, and Histriopolis or simply Istros/Histros. It is near the modern town of Istria.
It was the first urban settlement on today's Romanian territory, founded by Milesian settlers in the 7th century BC and was inhabited for at least 1,200 years.
It was under Roman rule from the 1st century AD in the Roman province of Moesia. The Tabula Peutingeriana shows it 11 miles from Tomis and 9 miles from Ad Stoma.
Wikipedia https://en.wikipedia.org/wiki/Histria_(ancient_city)
Address Romania
Coordinates 44°32'51.522" N 28°46'28.118" E