Today is Christmas in some of the various denominations of the Eastern church.
Image is the Hagia Sophia, built in 537 - one of the architectural wonders of the world, but not a Christian basilica since 1453, when Moslem invaders conquered Constantinople and slaughtered the Christians - men, women and children.
Speaking of which, here's a great time-line of what sorts of things prompted the Crusades. The Crusades were a reaction to Moslem imperialism, and Moslem imperialism never quit. It's part of their religion. As in Europe today, they will conquer without guns - when they can get away with it...but there is always a threat in the background.
And yes, the image of Hagia Sophia has been photoshopped to reveal its original grandeur. Across the inlet lie some of the fancy Istanbul neighborhoods overlooking the Bosporus - some of the most expensive real estate in the world.