Geographic Location
Panem exists in a post-apocalyptic future on the continent of North America. The exact details of what caused the collapse of the previous civilization are not fully explained in the series. What is known is that the nation was rebuilt from the ruins of the old world, with the Capitol positioned in the mountainous region that was once part of the central United States.
The Capitol and Districts
The Capitol serves as the governmental and cultural center of Panem. It is surrounded by 12 districts (originally 13 before District 13 supposedly went underground), each with different industries and purposes. The districts are spread across the remaining territory of North America, with District 1 through 12 positioned around the Capitol in various locations.
Districts and Their Locations
While Suzanne Collins did not provide an official detailed map in the books, she has indicated that the districts are scattered across what used to be North America. Districts closer to the Capitol tend to be wealthier and more privileged, while those farther away are poorer. District 12, where the main character Katniss Everdeen comes from, is located in what was once Appalachia.
The Fictional World
Panem is entirely fictional and exists only in Suzanne Collins's imagination and the adaptations of her books. The author created this world to tell a story about power, survival, and rebellion. No part of Panem actually exists in the real world, though the story uses real geographic references to ground the fictional nation in a recognizable setting. 
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