In Suhrawardi's works, the termHirqalya has been mentioned in two places. Before him, we do not know of any other author who has used this word.Hirqalya, on the one hand, is the name of a world (the Mundus Imaginalis, or 'imaginal world'), and on the other hand, is the name of an ideal city (and it seems that this city is the capital of that world). In this paper, it is proposed that Hirqalya is the name of a mythological city, which was established by the Kayanid prince, Siyavash. In Pahlavi books the name of that city, which can be described as an Iranian call polis, is Kang-diz. The characteristics of that strange city can be extracted from the various Pahlavi texts. As for the word Hirqalya, it can be said that the first part of Hirqalya is hir, which in Pahlavi and Persian means the sun and the second part of it isqalya, which means the castle (Kang-diz).