Bookland (imaginary place)
Apparently, when the international barcode system for all products (EAN) was being developed, they wanted to make it backwards compatible with the old book barcodes (ISBN). So they created an imaginary country called Bookland, so that books could be identified by ISBN without regard to their country of origin.
As if that weren’t enough, sheet music publishers had their own old barcode system and wanted in on EAN too, so there’s also an imaginary country called Musicland.
It’s a shame neither of these countries have approved my visa application yet, because I’d really love to visit!