The Icy Depths is a cave located beneath Crusaders' Coliseum. It is a small section of Azjol-Nerub directly under the Argent Tournament Grounds. After the final challenge of the Trial of the Crusader has been completed, the floor of the Coliseum shatters and the challengers fall into a subterranean lake. Anub'arak, in his second ressurection by the Lich King, can be found here, awaiting the challengers. After Anub'arak's defeat, Tirion Fordring proudly lauds his slayers and offers teleportation to the surface by one of the Argent Crusade's mages.
Gallery
Instance map of the Icy Depths of Azjol-Nerub under the Coliseum.
The hole in the Crusaders' Coliseum floor.
The pool in which players fall.
The arena where Anub'arak is fought.