Eureka, Utah
The city was named from the Greek word "eureka", meaning "I have found it!" The city and its history was explored on the show "Ghost Adventures" in 2018.
Erlking
It has been suggested, that the term may derive not from "elf-king" but from the name of "Herla", a figure in medieval English folklore, adapted as "Herlequin", "Hellequin" in medieval French, in origin the leader of the Wild Hunt, in French known as "maisnie Hellequin" "household of Hellequin" (and as such ultimately identical with Woden), but recast as a generic "devil" in the course of the Middle Ages (and incidentally, in the 16th century also the origin of the Harlequin character). Sometimes also associated is the character of "Herrequin", a ninth-century count of Boulogne of proverbial wickedness.