Bithynia and Thrace
The Marmara region was a corridor between Europe and Asia long before Istanbul became an imperial capital. Thracian tribes, Greek colonies on the Propontis and the Bithynian kingdom shaped the area; Rome later connected it with roads, bridges and new cities. Nicaea (İznik) hosted the First Ecumenical Council in 325 and the Second in 787; Nicomedia (İzmit) was an imperial residence; Perinthus (Marmara Ereğlisi) was a major Thracian and Roman port. Byzantium, founded as a Greek colony, became Constantinople in 330 and turned the region into the centre of a Mediterranean empire. The layers are still visible in city walls, aqueducts, churches, mosques and Ottoman bridges.
Where to see it
Opening hours, prices and transport change. Confirm details with the official venue before you go.