This is a picture here of a ziggurat, which was at the center of many of the Sumerian, and as we'll see, Mesopotamian cities. This would have required an incredible amount of labor to produce. And at the top of these, they had temples to their gods. And their gods, they had a polytheistic religion. And their gods took human form. Also, amongst the Sumerians, is where we think one of the first written languages developed. It wasn't the first, you also have the Egyptian hieroglyphics and we think written language emerged amongst the Harappans and the Indus Valley civilization and amongst the Chinese.