Real world locations such as South America, Guyana, India, America, Russia, China, the Pacific Ocean, Kyoto and Mt. Everest have all been referenced to exist in the mainline pokemon games.
>South America
Xatu's Pokedex entry states "In South America, it is said that its right eye sees the future and its left eye views the past."
>Guyana
Journal Entry in the Pokémon Mansion says
"Diary: July 5
Guyana, South America
A new Pokémon was discovered deep in the jungle."
>India
Multiple Pokedex entries reference Indian Elephants.
>America
The Fame Checker in FRLG about Lt. Surge calls him "The Lightning American". Also it says "Lt. Surge is rumored to have been a pilot while home in America.
He used the electricity generated by Pokémon to power his plane."
>Russia
In the Generation I games and Pokémon FireRed and LeafGreen, Scientist Taylor in the Silph Co. building mentions an international branch of Silph Co. In English, he states that the Tiksi branch of the company is "in Russian no-man's-land". In the Japanese version, he states that the Ponaya Tunguska branch is located "deep in Russia"
>China
Parasect's FireRed Pokédex entries mention that its spores are used in medicine in China.
>The Pacific Ocean
Poliwrath's Gold, Ruby, Sapphire, Emerald, Diamond, Pearl, Platinum, HeartGold, Black, White, Black 2, White 2 and X Pokédex entries mention its ability to swim the Pacific Ocean.
>Kyoto
In FireRed and LeafGreen, Blaine refers to Kyoto in the original Japanese version.
>Mt. Everest
Delibird's Ruby, Sapphire, and Emerald Pokédex entries explain that a Delibird helped a famous explorer reach the top of Mt. Everest.
