Get ready to have all your stereotypes against the place be shattered into pieces. Istanbul is composed of mostly young people and yet surrounded and grounded by traditions and important world history. The people are one of the most friendly and helpful people I've met in the world and it really comes off as genuine. Gotta see Hagia Sophia, Blue Mosque and Blue Cistern before you die.
Insider Tip:Start with Hagia Sophia in the morning followed by the Blue Mosque. They tend to be very touristy so being early means some of the people are still having breakfast at their hotels. Get the $85 Museum pass if you are planning to go to every single museum on their list. If not, better to pay one by one if you are also limited on time.