User blog comment:FairyRaven/Fairy Tail Chapters 338, 339, 340: Review and Commentary/@comment-5598380-20130706211549/@comment-7418318-20130707085026

Edolas is NOT above Earthland. It is a completely seperate parallel dimension/universe/whatever you want to call it.

While it does have floating islands, the continents on the ground below them are still part of Edolas. All the cities that were shown there, save for Extalia, were build down on the surface continents.