The Nile (iteru in Ancient Egyptian) was the lifeline of the ancient Egyptian civilization, with most of the population and all of the cities of Egypt resting along those parts of the Nile valley lying north of Aswan. The Nile has been the lifeline for Egyptian culture since the Stone Age. Climate change, or perhaps overgrazing, desiccated the pastoral lands of Egypt to form the Sahara desert, possibly as long ago as 8000 BC, and the inhabitants then presumably migrated to the river, where they developed a settled agricultural economy and a more centralized society. The river Nile froze twice in recorded history, in 829[6][7] and 1010.[8] The Eonile The present Nile is at least the fifth river that has flowed north from the Ethiopian Highlands. Satellite imagery was used to identify dry watercourses in the desert to the west of the Nile. An Eonile canyon, now filled by surface drift, represents an ancestral Nile called the Eonile that flowed during the later Miocene (23-5.3 million years before the present). The Eonile transported clastic sediments to the Mediterranean, where several gas fields have been discovered within these sediments. During the late-Miocene Messinian Salinity Crisis, when the Mediterranean Sea was a closed basin and evaporated empty or nearly so, the Nile cut its course down to the new base level until it was several hundred feet below world ocean level at Aswan and 8000 feet below Cairo. This huge canyon is now full of later sediment. Lake Tanganyika drained northwards into the Nile until the Virunga Volcanoes blocked its course in Rwanda. That would have made the Nile much longer, with its longest headwaters in northern Zambia. Role in the founding of Egyptian civilization Reconstruction of the Oikoumene (inhabited world) ancient map based on Herodotus' description of the world, circa 450 BCE. Enlarge Reconstruction of the Oikoumene (inhabited world) ancient map based on Herodotus' description of the world, circa 450 BCE. Sustenance played a crucial role in the founding of Egyptian civilization. The Nile is an unending source of sustenance. The Nile made the land surrounding it extremely fertile when it flooded or was inundated annually. The Egyptians were able to cultivate wheat and crops around the Nile, providing food for the general population. Also, the Nile’s water attracted game such as water buffalo; and after the Persians introduced them in the 7th century BC, camels. These animals could be killed for meat, or could be captured, tamed and used for ploughing — or in the camels' case, travelling. Water was vital to both people and livestock. The Nile was also a convenient and efficient way of transportation for people and goods. Egypt’s stability was one of the best structured in history. In fact, it might easily have surpassed many modern societies. This stability was an immediate result of the Nile’s fertility. The Nile also provided flax for trade. Wheat was also traded, a crucial crop in the Middle East where famine was very common. This trading system secured the diplomatic relationship Egypt had with other countries, and often contributed to Egypt's economic stability. Also, the Nile provided the resources such as food or money, to quickly and efficiently raise an army for offensive or defensive roles. The Nile played a major role in politics and social life. The pharaoh would supposedly flood the Nile, and in return for the life-giving water and crops, the peasants would cultivate the fertile soil and send a portion of the resources they had reaped to the Pharaoh. He or she would in turn use it for the wellbeing of Egyptian society. The Nile was a source of spiritual dimension. The Nile was so significant to the lifestyle of the Egyptians, that they created a god dedicated to the welfare of the Nile’s annual inundation. The god’s name was Hapi, and both he and the pharaoh were thought to control the flooding of the Nile River. Also, the Nile was considered as a causeway from life to death and afterlife. The east was thought of as a place of birth and growth, and the west was considered the place of death, as the god Ra, the sun, underwent birth, death, and resurrection each time he crossed the sky. Thus, all tombs were located west of the Nile, because the Egyptians believed that in order to enter the afterlife, they must be buried on the side that symbolized death. The Greek historian, Herodotus, wrote that ‘Egypt was the gift of the Nile’, and in a sense that is correct. Without the waters of the Nile River for irrigation, Egyptian civilization would probably have been short-lived. The Nile provided the elements that make a vigorous civilization, and contributed much to its lasting three thousand years. That far-reaching trade has been carried on along the Nile since ancient times can be seen from the Ishango bone, possibly the earliest known indication of Ancient Egyptian multiplication, which was discovered along the headwaters