Büyük Valide Han is a fortress of stone galleries wrapped around three linked courtyards, on a steep lane just below the Grand Bazaar. Step through the gate and the grandeur has gone soft with age: paint peels, cats doze on cracked marble, and behind low doorways sewing machines rattle over spools of thread and bolts of cloth. It is the largest of Istanbul's old caravanserais and it is still a working one, filled with textile ateliers rather than travellers and their animals.
For years a dim stair led up to the flat roof, and visitors paid a lira to stand on the domes for the view over Süleymaniye and the Golden Horn. Then the domes cracked under them and the door to the stair was sealed. Kösem Sultan, the queen mother who steered the empire from behind the throne, paid for the han. In one courtyard squats a blunt stone tower older than the building around it. Nothing here gets restored, because the rooms were split and sold until the han ended up with more than four hundred separate owners.