This booklet focuses on the Iron Age settlements and irrigation systems at Hili. The existence of wells and a falaj system provides evidence of water management by a prehistoric culture in a desert environment. Artefacts dating to 1000–600 BCE suggest the falaj at Hili 15 is the oldest in the world. It channelled water from the foothills of a mountain ridge five kilometres away to irrigate plants and crops, using tunnels and the force of gravity.

The growth of agriculture and the copper industry was accompanied by settlement expansion. Among the archaeological findings are a square building, mudbrick house and a room of storage jars at Hili 14, while Hili 17 has three houses with pottery kilns. At Hili 2, a village of 15 mudbrick houses and some communal clay tannours (ovens) have been discovered. There are large storage jars in many of the rooms, reflecting the economic growth and prosperity of the age.