A journey through this part of the world often has the quality of a pilgrimage, a physical and spiritual quest for the origins and realities of one's faith. After Constantine the Great declared Christianity the religion of the Roman Empire, the capital shifted from Rome to Byzantium. With the Ottoman conquest in 1453, the seat of the Patriarchate remained in Istanbul, and the city has been the capital of Orthodox Christianity ever since. The church commands a loyalty of some 250 million faithful. You'll begin your tour by visiting the Fener Patriarchate on the Golden Horn, the heart of Orthodox Christianity. Visit the Church of Panagia of Blachernae, the most well-known and celebrated shrine to the Holy Virgin. Then, see St. Savior in Chora, originally a Byzantine monastery with fantastic frescoes and mosaics depicting scenes from the Bible. Next, visit the Christ Pantocrator complex, one of the largest and best-organized from the Byzantine period. See Zoodochos Pege in Balikli, dedicated to the Mother of God, which holds a well-known miracle and the holy water spring believed to cure many illnesses. We will also visit St. Sergius and Bachus, and Hagia Sophia, which for many centuries was the largest church in Christendom, dedicated to Divine Wisdom. Finally, we arrive at Hagia Eirene, the patriarchal church, and the Church of St. Mary Pammacaristos, which housed the Patriarchate for some time after the conquest. Notes: Closings: Hagia Sophia on Mondays, St. Savior in Chora on Wednesdays and St. Mary Pamacaristos on Wednesdays.