Beyoglu is a great area to stay at, there are many small alleys with interesting shops and pretty cafes.
Eat:
Galata Bridge. Have some fish buns and beer on the lower level of the bridge.
Tarihi Karaköy Balikcisi.
A nice restaurant with view over the Bosporus; one specialty is fish wrapped in parchment paper.
Marko Pasa, Sadri Alsik Sok No.8. A cosy restaurant on the upper floor serving hand-made Manti (Turkish raviolis).
Mado Café, Istiklal Caddesi No:121. Perfect for some dessert and tea on the rooftop above the busy Istiklal Street.
Saray Café, Kuloğlu Mh., İstiklal Caddesi No:105. Try some Turkish breakfast, for example Börek (Turkish salty strudel).
Do & See:
Hammam. A relaxing luxurious Hamam experience in a beautiful building. Ladies are treated from the morning until 4p.m., men from 4.30 p.m. until
11.30p.m.
Grand Bazaar. Good for shopping souvenirs or
having some food in the backyard restaurants.
A Bosporus Boat Tour gives a closer look to the Asian side, e.g. with Sehir Hatlari.
The Blue Mosque – Sultanahmet
Camii. The mosque should not be entered during praying times (5x a day).
Topkapi Sarayi. Residence of the Ottoman Sultans with beautiful rooms for their harem.
Yerebatan Sarnici/Sarayi. An impressive cistern complex under Istanbul with nice sculptures as the Medusa heads.
Hagia Sophia/Ayasofya. Do queue in two lines: one to buy tickets, one to enter.