Seleucia on Hedyphon was the name of the ancient Assyrian city of Arrapha during the Hellenistic period (331–129 BCE). It was in eastern Assyria on the bank of the river Hedyphon (Greek: Ἡδυφών).
Known to the Assyrians and to Claudius Ptolemy as Arrapha and Korkoura, the city flourished during the 11th and 10th centuries BCE. Familiar from tales of the saint's lives in East as Beth-Seleucia, it was a city related to many martyrs of the orthodox Christian church. The bishop of the city was John, who was mentioned in the chronicles of king Shapur.
In the Hellenistic period the city was renamed Seleucia, for Seleucus I Nicator or one of his successors. The locals called it Karkha D- Bet Slokh (citadel of the Seleucid dynasty). Today it is located in the city of Kirkuk in northeast Iraq.