The first time I went to Istanbul, I didn't go to the Hagia Sophia. I didn't go to the Blue Mosque. I’m embarrassed to admit this, but I do have a good excuse: the city itself is so gorgeous, so walkable (sometimes by necessity: the traffic runs from bad to dreadful) that it can seem a shame to leave the streets and go inside. On my most recent trip there, however, I did go to the Hagia Sophia, the Blue Mosque, and, of course, the Grand Bazaar. But along with spending time in Sultanahmet—the…