İznik is one of the districts of Bursa. Towards the end of the 4th century, it was reestablished by Antigonos Monophtalmos, an old settlement with the name "Antigoneia". Later, Lysimakhos renamed the city as Nikaia, after his wife. The city is one of the small settlements in a territory dominated by a heterogeneous public structure during the Bithynia Kingdom. During the Roman Imperial period, gained importance as the center of the Province of Bithynia et Pontus and possibly one of the cities where the provincial governor lived, together with the Imperium Romanum, which spread all over the Mediterranean. In the period of the Eastern Roman Empire, which emerged with the division of the Empire in the following Late Antiquity, Nikaia was the hinterland of the capital Constantinople and Nicomedia. The Eastern Roman Emperor Theodore Lasgaris fled to İznik with his nature after İstanbul was invaded by the Latins in 1204 and founded the Byzantine Empire of İznik (1204/1265). İznik, historically known as Nicea, lies on the eastern shores of lake. The city was surrounded by 5 km of walls about 1m. high İznik. In turn surrounded by a double ditch on land also included over 100 towers. Large gates on the three landbound sides of the walls hall provided the only entrance to the city. It is known that the city was the capital of the Seldjouk State for a while during the establishment phase. Nicea was an important center in late Roman and Byzantian times. Notably, as the sites of two councils of the early Christian Church, 325 and 787 AD, have met in Nicea is a very important place for the Christians to visit. In 1331, Ottomans captured the city from the Byzantines and became the capital for Ottomans for a short period of time.Early morning departure from İstanbul. It is thought that there was a pagan temple built by the order of Roman Emperor Commodos. In 394 AD., with the decree of Emperor Theodosius warship in all pagan temples was banned and basilical churches were built.Early morning departure from İstanbul and first visit to Hagia Sophia Church. The most important historical structure of the city for Christian tourists for religious purposes is the Saint Sophia Church commissoned by Justinian I during the 6th century. İznik, which was captured by the Ottomans in 1331, served as the capital of the Ottoman Empire for a very short time . İznik tiles, which became famous all over the world in the 16th century was used for decorating all important mosques. It is far ahead of its competitors today. Shopping possibility from producer shops, a fish lunch by the lakeside. In 2014, another new and very important historical find by archaeologist Prof. Dr. Mustafa Şahin is the Neophytos Basilica that dates back to 1500 years, which was announced as the “Greatest Discovery Of The Year” by the Archaeological Institute Of America in 2014. There are the clearly visible remains of the Neophytos Basilica that have slipped into the lake today. The 1st Consul which convened in İznik with the meeting of 318 bishops in 325 AD., is estimated to have been convened in this basilica named after St. Neophytos is very probable. Especially, the Vatican and all Christiandom started to celebrate the 1700th year of the 3rd. Consul Meeting in İznik of 325 AD. in coming 2025. The opening of the basilica as “The Underwater Archaeology Museum” to visitors will make İznik a very important region which is already famed with the city walls & doors, museums and historical structures will draw the whole world's attention and no doubt, be one of Türkiye’s most important centers. There are also Hacı Özbek Mosque and İznik Yeşil Mosque as a good samples of Ottoman architecture. İznik is a great city with many opportunities in terms of historical importance to attract foreign tourists. Evening return back to İstanbul.