You need some downtime today.
Prince Islands is the perfect way to end your stay in Istanbul. Take the ferry near the Spice Market, and the Galata bridge, and head over to one of the best kept secrets of Turkey. A day on the beach is exactly what the doctor orders after a jam-packed 3 days in Istanbul.
Hidden Gem: Spice Bazaar. This is right where you catch the ferry across to the island, although it’s a better idea to head here after spending an afternoon on the beach. This also to perfect place to stock up on your coffee, and spices- esp saffron (be very cautious about the quality here). Oh and don’t forget to pick up some Turkish Delight!