Hun according to me, if it is a fictitious story you can surely mention anything you want, you can let your imagination go wild, you can let all your creativity out and bring any creature, place, superpower in your story.
But if you still have doubts about people googling ' "If this city actually existed in US' you can mention it in the beginning of the book to prevent any confusions.
Feel free to write anything you want hun, IT'S YOUR BOOK !!!
Hope this helps!
