In the Citadel,
we lead different lives
Game of Thrones Season 7, Episode 1
You are a maester of the Citadel,
Game of Thrones Season 2, Episode 6
The Citadel doesn't admit women.
Game of Thrones Season 6, Episode 3
A raven came from the Citadel.
Game of Thrones Season 6, Episode 10
the Citadel to give him back his chain.
Game of Thrones Season 3, Episode 7