In the Stephen King book The Stand, Trashcan Man is instructed by Randall Flagg to meet him in Cibola, which is later revealed to be Las Vegas.
Cíbola was discovered beneath Mount Rushmore in National Treasure: Book of Secrets, a 2007 film starring Nicolas Cage and Diane Kruger.
https://en.wikipedia.org/wiki/Seven_Cities_of_Gold- I was looking this up and found this instead