"The Land of the Dead"

The land of the dead in the Amber Soyglass shares some characteristics with the underworld in Greek mythology. The biggest similarity is that there is an old man who ferries the dead across a body of water to the land of the dead. In Greek mythology this man's name is Charon (I think) but he is unamed in the Amber Spyglass. Another similarity is that both concepts of the world of the dead are underground.