Where is Chalcedon?
Chalcedon
The site of Chalcedon is located on a small peninsula on the north coast of the Sea of Marmara, near the mouth of the Bosphorus. A stream, called the Chalcis or Chalcedon in antiquity and now known as the Kurbağalıdere (Turkish: "stream with frogs"), flows into Fenerbahçe bay. There Greek colonists from Megara in Attica founded the settlement of Chalcedon in 685 BC, some seventeen years before Byzantium.
Chaldean Catholics
The current patriarch considers Baghdad as the principal city of his see. His title of "Patriarch of Babylon" results from the identification of Baghdad with ancient Babylon (however Baghdad is 55 miles north of the ancient city of Babylon and corresponds to northern Babylonia). However, the Chaldean patriarch resides habitually at Mosul in the north, and reserves for himself the direct administration of this diocese and that of Baghdad.