The birth of the Appalachian ranges, estimated at 680 million years ago, marks the first of several mountain-building plate collisions that culminated in the construction of the supercontinent Pangaea with the Appalachians near the center. Because North America and Africa were once connected, the Appalachians form part of the same mountain chain as the Atlas Mountains of Morocco and Algeria. (via)

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The birth of the Appalachian Mountains predates the formation of the American continent.