What should I do if I stop at Istanbul Ataturk Airport for 9 hours?

First of all, private passports are not allowed to enter the country, and official passports can be exempted from entry.

If you have an official passport, you can enter the country directly. Ataturk Airport is more than 1 hour by subway from Hamad District, Sultan, a tourist area in Istanbul. When you get off the subway, you can directly visit two important scenic spots, Hagia Sophia and Blue Mosque. If you don't go in, you will have enough time to take pictures and buy some handicrafts. The main attractions are all around these two cathedrals.