The Netherworld is an alternate plane of existence in The Runelords novel series by David Farland. The Netherworld is not the equivalent of some mythological underworld, but a realm fundamental to the make-up of the cosmology of the setting.
The Netherworld is a fictional autonomous neighborhood of the city of Chicago in the DC Comics universe. It first appears in Hawkworld #30 (January 19893), it was created by John Ostrander and Tim Truman.