The reason that major cities are where they are is because either there's a ton of traffic that flows through the area OR because they were the highest, easiest

The reason that major cities are where they are is because either there's a ton of traffic that flows through the area OR because they were the highest, easiest point to build on near a major source of fresh water. So no, they're not going to just appear because you build a city there. That's not how cities or infrastructure work.