It is thanks to the work of these archaeologists that we have some idea of the development of Ain Ghazal over the millennia. Based on the archaeological evidence, Ain Ghazal was first occupied around 7250 BC, during a period known as the Pre-Pottery Neolithic . At that time, the settlement consisted of only several hundred inhabitants, who lived in individual houses. These houses were made of stone covered with mud and lime plaster and painted with a red pigment.
A change in the settlement occurred around the beginning of the 7th millennium BC. At that time, the population of Ain Ghazal rose rapidly from an influx of new inhabitants. Consequently, the population of the settlement almost doubled in size to 1,600 people.