In the fictional world of Middle-earth created by J. R. R. Tolkien, Rhûn was a large region of eastern Middle-earth. Rhûn (which is also the Elvish word for "east") was the name used for all lands lying east of Rhovanion, around and beyond the inland Sea of Rhûn, whence came many attacks on Gondor and its allies during the Third Age of Middle-earth.
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