Asia
The coastal periphery was home to some of the world's earliest known civilizations, each of them developing around fertile river valleys. The civilizations in Mesopotamia, the Indus Valley and the Yellow River shared many similarities. These civilizations may well have exchanged technologies and ideas such as mathematics and the wheel. Other innovations, such as writing, seem to have been developed individually in each area. Cities, states and empires developed in these lowlands.
Dilmun
The Dilmun civilization was the centre of commercial activities linking traditional agriculture of the land—then utterly fertile due to artesian wells that have dried since, and due to a much wetter climate—with maritime trade between diverse regions such as the Meluhha (Indus River Valley), Magan (Oman), and Mesopotamia. The Dilmun civilization is mentioned first in Sumerian cuneiform clay tablets dated to the late third millennium BC, found in the temple of goddess Inanna, in the city of Uruk. The adjective Dilmun is used to describe a type of axe and one specific official; in addition there are lists of rations of wool issued to people connected with Dilmun.