Where is the location of Celestia?

Excuse me, could you possibly enlighten me on a matter of geographical curiosity? I've been doing some research and have stumbled upon a reference to a place named Celestia, but I'm afraid I'm at a loss as to its precise whereabouts. Would you happen to know where Celestia is located? Is it a real-world destination, or perhaps a mythical or fictional place? Any information you could provide would be greatly appreciated. Thank you in advance for your assistance in this matter.