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Celadon University (Japanese: タマムシシティ大学 Tamamushi City University) is a university located in Celadon City.
In the anime
Celadon University is referred to multiple times in the anime. In Chikorita's Big Upset, the episode's Nurse Joy mentions that she studied a degree in Pokémon psychology at Celadon University. In Fossil Fools, it is revealed that Professor Oak used to teach there, and Foster was one of his top students.
In the manga
In Pokémon Get da ze!
Celadon University is the setting of Challenge at Tamamushi University! in Pokémon Get da ze!, where it is revealed that Gym Leader Erika teaches here in addition to her duties as the Celadon Gym Leader. Tomoaki Imakuni appears as an art student there.
In Pokémon Adventures
The university also appears in this canon, first appearing in Whacked by Marowak. Erika lectures here sometimes in addition to her duties as a Gym Leader.