
The Citadel doesn't admit women.
Game of Thrones Season 6, Episode 3

that had him expelled
from the Citadel, Your Grace.
Game of Thrones Season 4, Episode 10

The Citadel has the world's greatest library.
Game of Thrones Season 5, Episode 10

At the Citadel,
I transcribed a High Septon's diary.
Game of Thrones Season 7, Episode 7

So, why did the Citadel take your chain?
Game of Thrones Season 3, Episode 7