Jump City is a major metropolitan city on the west coast of the United States of America near the San Francisco Bay area. It's hometown superheroes are the Teen Titans superhero team.
Killer Moth's hideout is a giant cocoon under the Bay Bridge in Jump City. Within the cocoon is Moth's high-tech equipment and laboratory and living quarters. Cashing in a reward for Silkie, Robin, Beast Boy and Cyborg piloted the T-Jet right into the cocoon and plowed through Moth's newly released giant moths. Raven and Starfire later teleported into the cocoon to check on Silkie. They watched as Moth threw him into a pool of chemicals but Silkie emerged even more cute. Some time later, Moth faked an emergency distress call and lured the Titans to his cocoon to mutate them with his Bug Beam.