The union of Upper and Lower Egypt was made possible by the Nile River's flow from south to north, connecting the two regions.
The geographic feature that made possible the union of Upper and Lower Egypt was the Nile River. The Nile flows from the south (Upper Egypt) to the north into the Mediterranean Sea, forming the Nile Delta (Lower Egypt). This geographical characteristic facilitated communication, transportation, and the eventual unification of the two regions.
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