Known as the City of Wailing Demons, this mighty prison belonged to Ken-Oh and was under the jurisdiction of the cruel warden, Uighur. Cassandra was used to imprison martial artists who had forfeited their ancient scrolls to Ken-Oh in his goal to create the ultimate martial art. It was also the prison for Raoh's brother, Toki, who Raoh incarcerated as a threat to his conquest.
The only escape from its walls was death, and it was only once Kenshiro defeated Uighur and his forces, that its terrible legend finally came to an end.
In the end of the battle with Uighur, he warns that Kenshiro and Toki will never meet before dying of the Hokuto Shinken injuries given to him.
In the anime, he says in the prison will be reduced to nothingness, meaning wired explosives would tear down the prison soon.
1986 movie
In the 1986 theatrical movie, Yuria was imprisoned in Cassandra, and it sets the stage for Kenshiro & Raoh's battle.