This question already has an answer here:
After seeing this article about what Middle-earth would look like from space, and reading one of the first comments, which indicates that there are hints that Middle-earth is flat, I'm left with what seems to be an obvious question:
Where is Middle-earth? And is it flat?
Is Middle-earth supposed to be on Earth sometime before recorded history, or on islands or continents that were lost due to the motion of tectonic plates? Is it supposed to be in a mis-shapen Europe during the historical period that would match the development in Middle-earth?
Or is it supposed to be on a different planet or location entirely? And if so, what are the indications that it is flat? (And is it flat or curved?)