Can you pinpoint on a satellite map the 100 most populous American cities?

The rules of this free game are very simple: we give you the name of a city, and you have to point it out on the map.
Are you below 100 miles? You continue.
Are you above? Game over!

A simple concept for an actually quite hard quiz.
Sure you know where New-York or Los Angeles are, but Des Moines? Where the hell is Des Moines?!?