The Nile River. Possibly the longest river in the world, but certainly the most storied in history. Without the Nile, the civilizaiton of Ancient Egypt would have never existed. To the Ancient Greeks and Romans the source of the Nile was a question that vexxed them for centuries. This quest to find the source of the river would be the longest running question in geographic history. And its answer wouldn't come until only 160 years ago.