Unknown Regions

The Unknown Regions are the areas surrounding the city of Ember, named so because they are devoid of any life and have never been explored. There was no light in the Unknown Regions, natural or otherwise. People who explored the Unknown Regions either disappeared, or returned within minutes out of fear.

Description
Beyond the greenhouses, beehives, and trash heaps was a massive crevasse about fifteen feet wide but over a hundred feet deep, dug by Cole using dynamite sticks. If any person tried to enter or exit Ember via the Unknown Regions, they would fall into the pit and die. Cole then would exile their family to the edge of the city. These families provided support to the Communist Party of Ember. While it was believed that the Unknown Regions went on forever in all directions, they actually ended at the edge of the cavern that Ember was constructed in. At one point, a switchback ramp was carved out of the rock during Ember's construction, and was the only known entrance to the city.

Usage
The Unknown Regions were also where the people of Ember left their dead. The body was carried past the trash heaps, a song was sung, and then the body was left to the process of decomposition.