In Arabic, Egypt is sometimes called Umm Al-Duniya, or the mother of the world. The Nile River, which waters the country, could give it some stiff competition for that title. Considered the world’s longest river, the Nile’s waters have fostered human civilization for thousands of years. No country knows that better than Egypt: The nation’s survival depends on the river, and has since the time of the Pharaohs. While the Nile is a reference …