If you hadn’t seen St.Sophia in Istanbul, you wouldn’t have discovered real history indeed. History of Christianty is related to development of Constantinapole and Nicea because Christianty and Holy Bible became universal with councils of Constantinapole and Nicea.
St.Sophia is avery important figure in Christianty because it is still the biggest church of Orthodox world and also it is one of the holy churches of Christian world. StSophia was built three times. It was the last church and you can see the remains of other churches next to St.Sophia. First church was built with wooden roof and it was burned by an uprising in the city. Second one was also collapsed during Nika rebellion in 532. According to the legend, Emperor Justinanius saw the architecture of new church in his dream. So he had this church built up to this plan. It was opened in 537. There are secret tunnels and graves under the new St.Sophia.
St.Sophia is like a time capsule because it has features from every period. The dome was just rebuilt after the earthquake. It has the biggest dome and it was replaced on big walls. It was ruined by Crusaders during IV. Crusader campaign.
After the conquest of the city by Turks, St.Sophia was rebuilt as a mosque till the republic of Turkey was founded. It was converted into a museum in 1936.
You can feel the rituals of crownings and spirit of Byzantines. Also you can feel the violence by witnessing the grave of Latin commander inside the St.Sophia. It is exactly true place to travel in time.