From Bulbapedia, the community-driven Pokémon encyclopedia.
Each location in the Generation VI games has its own identification number used internally by the game. They are enumerated here, in order. Locations such as routes with alternate names have their alternate names listed as an index number after the main location. Locations lacking an alternate name have the following index number blank.
Locations with index numbers up to 00168 appeared in Pokémon X and Y; those with index numbers between 00170 and 00354, as well as the individual index number 60004, are exclusive to Pokémon Omega Ruby and Alpha Sapphire. Index numbers between 00355 and 30000, 30012 and 40000, 40080 and 60000, and above 60004 are filled with null data. If a Pokémon references an index number for met location that does not exist in that game, it will be displayed in that game as Faraway place.
Pokémon Omega Ruby and Alpha Sapphire have all location headers programmed in that Pokémon X and Y do; however, "a Day-Care Couple" and "Day Care helpers" appear as the other in the other games.
If a Pokémon is transported through Poké Transporter, then its met location and Egg met location stay the same as they were in Generation V instead of changing to 30001 (Link Trade); however, this is not visible in-game, as the Pokémon's game of origin dictates the displayed met location in these cases.