And then eventually they're going to be able to trade with internal Africa as they look for supplies to build their most awesome pyramids. They're going to need limestone, they're going to need gold, they're going to need ivory, they're going to need things they don't have, which they're going to have to get. So geography is really important, make sure that you look at that map one more time and you get the big idea that the Nile is the heartbeat of Egypt as we now take a look at the old kingdom of ancient Egyptian society. Are you ready to unify? Good. But we need something to unify. And considering from about 5000 BCE to about 3200 BCE, which is like 2000 years, there isn't really a kingdom in Egypt.