The Dead Lands are where the Great Re:Duction began. In Fire World it is said to be a place of banishement and anyone sent there will never be seen again. Against her will, Eliza is taken there for training to be an Aunt. Eliza made an egg from clay there, and it birthed Penny.
At the time the quake happened Harlan was banished and found a civalization there. He met Mathew Lefarr there and soon becane friends. He also saw the spirit of Gawain there and found his claw.