Thalarion is a fictional location in H. P. Lovecraft's Dreamlands. The name refers to one of the largest cities in the Dreamlands, known as the "City of a Thousand Wonders", where all the mysteries that man has striven in vain to fathom reside. Its walls are grim and grey, with a great carven gate called Akariel, and the spires of its temples reach to the sky so that none might behold their peaks. The dream traveler Basil Elton described the city as "fascinating yet repellent". It is implied that any human who enters dies or is transformed somehow, and in the city are said to "walk only daemons and mad things that are no longer men". The city is ruled by an entity known as the eidolon Lathi. Thalarion is mentioned in The Dream Quest of Unknown Kadath and The White Ship.
Lovecraft, Howard P. (1985) . "The Dream-Quest of Unknown Kadath". In S.T. Joshi (ed.). At the Mountains of Madness and Other Novels (7th corrected printing ed.). Sauk City, WI: Arkham House. ISBN0-87054-038-6. Definitive version from original manuscripts.