Called Calno, Isaiah 10:9 and Canneh, Ezekiel 27:23, one of Nimrod’s cities, Genesis 10:10, and afterwards called Ctesiphon; it lay on the east bank of the Tigris opposite Seleucia, twenty miles below Bagdad. Ctesiphon was a winter residence of the Parthian kings. Nothing now remains but the ruins of a palace and mounds of rubbish.
Source: ATS Bible Dictionary
Calneh
Fort, one of the four cities founded by Nimrod (Genesis 10:10). It is the modern Niffer, a lofty mound of earth and rubbish situated in the marshes on the left, i.e., the east, bank of the Euphrates, but 30 miles distant from its present course, and about 60 miles south-south-east from Babylon. It is mentioned as one of the towns with which Tyre carried on trade. It was finally taken and probably destroyed by one of the Assyrian kings (Amos 6:2). It is called Calno (Isaiah 10:9) and Canneh (Ezekiel 27:23).