Laputa.
Laputa is a legendary flying city, once hosting a very powerful civilization before it mysteriously vanished. Most of people of the Earth view the tale as a myth, although some have insisted to have proof of its existence, such as Pazu's father.
Etymology[]
The name for Laputa was derived from Jonathan Swift's famed book Gulliver's Travels, which also featured a floating city named Laputa as well.
The word Laputa has negative meaning in Spanish language, where "La Puta" essentially means "The Whore."