Orașul Niceea, sau în grecește Νίκαια, care în zilele noastre se numește Iznik în limba turcă, a fost
locul unde s-au ținut doua [[Sinoade Ecumenice]] ale [[Biserica Ortodoxă|Bisericii Creștine]] timpurii. În timpul ocupației
Constantinopolului, după capturarea sa în anul 1204 la a patra cruciadă, Niceea
a fost capitala Imperiului Nicean, cel mai puternic dintre statele bizantine care au supraviețuit.
Located near the eastern end of the Sea of Marmara on what is now Lake Iznik, Nicea was built on the site that was originally called Ancore/ Helicore. A town called Antigoneia was built on this site late in the fourth century before [[Christ]] by the Macadonian king Antigonus I Monophthalmus, who had been one of Alexander the Great’s generals. There are two version of how Nicea received its name. In one story the town later came under the control of Lysimachus who rename the town Nicea after his wife. In another account it was founded by Alexander’s men from Nicea near Thermopylae.
Nicea attained commercial importance as it was on the crossroads between Galatia and Phrygia. In this regard Nicea was a rival of nearby [[Nicomedia]]. Its importance carried through and continued after the founding of [[ Constantinople]] as the capital of the Eastern Empire. The nearness of Nicea to Constantinople appeared to have contributed to the use of the city in the important events involving the Church and the Roman emperors. It was only 43 miles (70 km) from the capital. Nicea was encircled by a wall that was 14, 520 feet (4,426 meters) long. The wall is almost entirely intact today.
Nicea was the site of the [[First Ecumenical Council|First]], in 325, and, in 787, the [[Seventh Ecumenical Council|Seventh Ecumenical]] Councils. These councils are also known as the First and Second Councils of Nicea. The First Council addressed the [[Arianism|Arian]] [[heresy]] and more clearly defined the concept of the Trinity which the council expressed in the [[Nicene Creed]]. The second council addressed the issues relating to [[icon]]s raised by the iconoclasts, expressing their proper use for veneration.
The first council was held in the “Senatus Palace” that now lays beneath the waters of Lake Iznik. The seventh council was held in the Church of Hagia Sophia that was built by [[Justinian]] in the sixth century, This [[church]] was modeled after the [[Hagia Sophia (Constantinople)|Hagia Sophia]] in Constantinople. Located in the center of the city, Hagia Sophia was turned into a mosque by the Turks and renamed Orhan Ghazi Mosque in 1331. Over the years this structure has been badly damaged by earthquakes and fires. Some mosaics and a fresco of Christ, however, remain. The Church of the Dormition, a major church in Nicea, was destroyed by the Turks in 1922. This church was decorated with many fine mosaics that dated from the ninth century.