From Kook Science

Hyperborea (Ancient Greek: Ὑπερβόρε(ι)οι [hyperbóre(ː)ɔi̯]; "beyond Boreas (the North Wind)") was the name given by Greek scholars and poets of classical antiquity to an unknown land (terra incognita) they described as being situated in the distant north, a home to a long-lived, gigantic peoples. Varied authors, classical and modern, have suggested the location of Hyperborea to be anywhere from the Kazakh Steppe to Scandinavia, Britain to Siberia, and even within the Hollow Earth.