Tower of the Citadel
The Citadel is the seat of the Order of Maesters, the learned men who advise the lords of the Seven Kingdoms on matters scientific, medical, and historical. It is located in the city of Oldtown in the far southwest of the continent.
The Citadel was founded many centuries ago to promote and increase learning and knowledge in Westeros. It is administered by the Conclave, the ruling council of archmaesters. The Citadel is also were young men from the entire continent are trained to become Maesters (x).
Widow’s blood is a poison. It is named so for its color. It shuts down the bladder and bowels until the person dies from the body’s own poisons (x).