For gamers, Pokémon Go is remarkable thanks to its massive popularity after only a week’s release, and its innovative combination of a retro game beloved of 90s kids (Pokémon) with the latest in Augmented Reality (AR).

For us, it’s interesting because of the maps. 

While the game has only been officially released in the US and Australia, users have played it all over the world – from my road in Harringay, north London, to the front line of the war against Isis in Mosul, where a former US marine volunteering with Christian militia managed to catch a Squirtle. The game has inserted Pokémon all over the world map, plus “Pokéspots” and “Gyms” where you can lure extra creatures or make them fight each other.

Nintendo seems to have taken the bulk of its map information for the game from Ingress, a previous, much less popular game from Niantic, the company which worked with Nintendo on the game. An Atlantic piece notes that “portals” from this game seem to match the Pokéspots in Pokémon Go. It also notes, though, that the game doesn’t credit any street map producer, such as Google or OpenStreetMaps – unusual for a map-based game. 

A player locates a Goldeen. Image: Getty.

However, John Hanke, the CEO and founder of Niantic, was one of the founders of Keyhole, which created Google Earth (and may give us a clue as to the maps’ source). He told Mashable that the Pokémon Go team mined Google geotagged photos for public art which could be used as Pokéspots. Others were submitted by Ingress players and then approved by game moderators. Some of the most popular portals from Ingress were then chosen as “gyms” for the new game. 

The benefit of this method is that these are places people (well, Ingress players at least) do visit, and implies they should be easily accessible. This doesn’t mean it’s foolproof: several people have already reported that their homes were marked as gyms on the game, meaning random gamers turned up outside their doors or lurk about outside. Given you can “own” a gym on the game, some opened with the slightly worrying line: “this is my gym.” 

Pokémon themselves are scattered fairly randomly in the game, though water Pokémon appear near or on water. Hanke told Mashable that another, secret set of geographical data was used to match Pokémon to their locations:  “That gets into more [geographic information system]-type of data… and we utilise that to map Pokémon species to appropriate habitats.” 

Again, this does lay the game open to goofs. Today, there were reports that a poison gas “Koffing” Pokémon appears when you visit the Holocaust museum in Washington DC.

One final mapping fact: in 2014 Google ran an April Fools Day game in which you could locate Pokémon on its maps feature. The game went down so well that Hanke reportedly wondered whether it could take off as a real game, with the hunt for Pokémon  transposed onto the real world. Nearly eight million downloads later, looks like he was right .