was around 10 hours.
Istanbul is fantastic and the complete opposite of East Africa.
Incredible infrastructure and public transportation. Appears to be close to full employment. The best combination of old and new I have seen anywhere.
If you go, try to stay in the Sultanahmet (the old walled city). I stayed in a small boutique hotel:
http://www.hotelamira.com/
Walking distance to the major sites and the trams. Wonderful restaurants and night life.
The people love tourists and treat you very well. Despite language barriers, everyone really tries to help you.
The blue mosque, the spice market, boat ride in the Bosphorus, the long street in the new section with side streets full of fish markets, cheese markets, etc.
A very friendly and easy place for women traveling alone. The calls to prayer from all the mosques is magical.
I have not one negative thing to say about it.
Here is an article I used as a guide and it's great.
http://www.independent.co.uk/travel/48-hours-in/48-hours-istanbul-2367150.html