If you look at the map, you can see Samosata up north on the Euphrates, Ressaina between Euphrates and Tigris and Zeugma to the west. Tharrana is next to the ci

If you look at the map, you can see Samosata up north on the Euphrates, Ressaina between Euphrates and Tigris and Zeugma to the west. Tharrana is next to the circular lake with the island. https://en.wikipedia.org/wiki/Samosata https://en.wikipedia.org/wiki/Samosata is the modern city of Samsat https://en.wikipedia.org/wiki/Rhesaina https://en.wikipedia.org/wiki/Rhesaina is Ressaina (see http://www.perseus.tufts.edu/hopper/text?doc=Perseus:text:1999.04.0064:id=rhesaena-geo http://www.perseus.tufts.edu/hopper/text?doc=Perseus:text:19...) https://en.wikipedia.org/wiki/Zeugma,_Commagene https://en.wikipedia.org/wiki/Zeugma,_Commagene Zeugma is near modern-day Gaziantep The location of historic Tharrana is apparently not finally known. Harran, Turkey is one possibility mentioned at http://www.euratlas.net/cartogra/peutinger/10_mesopotamia/mesopotamia_5_3.html http://www.euratlas.net/cartogra/peutinger/10_mesopotamia/me.... Since all reference points are in Turkey or Syria, best guess is that the cirular lake with the island is Al Jaboul Lake, 36.024360"N, 37.610087"E. It used to be a tributary to the Euphrates but no source I could find states exactly when that changed.