The fertile crescent was an area with ancient people built large here.

The Fertile Crescent was an area with agriculture. Ancient people built large cities here.

Explanation:

Most archaeologists argue that the first large scale civilizations developed in Mesopotamia or the Fertile Crescent around 10 000 to 7500 BCE, after the Neolithic Revolution, which marked the transition from hunting and gathering to a more sedentary and agricultural means of livelihood. The first cities were Ur, Eridu, and Uruk. Mesopotamia was located around the Tigris–Euphrates river system in what is today Iraq, Kuwait, Syria, and southeastern Turkey. The wheel was invented in Mesopotamia, and there is the first evidence of mathematics and astronomy.  

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