Nicaea (/naɪˈsiːə/; Greek: Νίκαια) was a Hellenic city in northwestern Anatolia, and is primarily known as the site of the First and Second Councils of Nicaea (the first and seventh Ecumenical councils in the early history of the Church), the Nicene Creed (which comes from the First Council), and as the capital city of the Empire of Nicaea.
Nicaea served as the interim capital city of the Byzantine Empire between 1204 and 1261, following the Fourth Crusade in 1204, until the recapture of Constantinople by the Byzantines in 1261.
The ancient city is located within modern Iznik, Turkey, and is situated in a fertile basin at the eastern end of Lake Ascanius, bounded by ranges of hills to the north and south. It is situated with its west wall rising from the lake itself, providing both protection from siege from that direction, as well as a source of supplies which would be difficult to cut off. The lake is large enough that it could not be blockaded from the land easily, and the city was large enough to make any attempt to reach the harbour from shore-based siege weapons very difficult.
The ancient city is surrounded on all sides by 5 km (3 mi) of walls about 10 m (33 ft) high. These are in turn surrounded by a double ditch on the land portions, and also included over 100 towers in various locations. Large gates on the three landbound sides of the walls provided the only entrance to the city.
Today the walls have been pierced in many places for roads, but much of the early work survives and, as a result, it is a major tourist destination.
Read more about Nicaea: Ruins, Contemporary Influence, Notable People