Warden's Cage is an Illidari Servitor-run prison located west of the Black Temple in Shadowmoon Valley. As its name implies, it is where Warden Maiev Shadowsong, the former jailor of Illidan Stormrage, is held prisoner by the Betrayer's Broken servitors led by Akama himself.
Warden's Cage Digsite
Warden's Cage is an archaeology dig site. Both draenei and orc archaeology fragments can be found here, though all fragments from one 3-dig session will be of the same type.