Discover the old, religious Istanbul. Visit the big mosque and the mausoleum of sultan Mehmet II, named the Conqueror (Fatih in Turkish) because he conquered the magnificent Christian city of Constantinople in 1453.
You can see surviving gates where the Turkish soldiers entered Constantinople and the Gul mosque, a former church of the saint and martyred nun Theodosia, who was for seven centuries the patron saint of Constantinople.
Go up the hill and visit the sultan Sarnici, an 1600 old cistern that was a garbage dump until recently and has been renovated and gotten a new life as a meeting room for wedding parties, seminars, receptions and gala dinners.
Visit the Sultan Selim mosque on the Fifth Hill, that has a charming courtyard with an extensive and magnificent view of the Golden Horn. Selim ruled for only eight years. Still he is one of the most important Sultans. He doubled the extent of the Ottoman Empire and killed all his brothers – except one – and all his cousins.
Go to the Carsamba neighborhood as well, the most conservative part of the old city where most of the people are orthodox Muslims in very conservative clothes.