Three Fabulous Cities

Although the planet Krypton was destroyed, one Kryptonian city, Kandor, had been miniaturized and removed and still survives with all its inhabitants in a bottle. (DC Comics.)

The Golden Age of Baghdad will last as long as mankind because Haroun al Raschid gave it to Morpheus who keeps it in a bottle in the Dreaming. (Neil Gaiman's The Sandman, published by DC.)

The city of Ys is known only in legend and fiction because its Gods not only destroyed it but also concealed it behind a "Veil." (The King Of Ys by Poul and Karen Anderson.)

See also Great Cities.