Middle-earth is the translation of the Middle English middel-erde , which developed from Old English middangeard . The term refers to the the habitable lands of men between heaven and the underworld. Less formally, the term "Middle-earth" often refers to the 'mortal' lands where the stories of author J. R. R. Tolkien take place, as opposed to Aman , where the angelic Valar live together with most of the High Elves .
Tolkien said that his Middle-earth is our Earth , but in a fictional period in the past, estimating the end of the Third Age to about 6,000 years before his own time.
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