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 is no light in the Unknown Regions, natural or otherwise. People who explore the Unknown Regions either dissapear, or return within minutes out of fear. Beyond the greenhouses, beehives and trash heaps is a massive crevasse about fifteen feet wide but over a hundred feet deep. If any person tries to enter or exit Ember via the Unknown Regions, they fall into the pit and are killed. The Unknown Regions are also where the people of Ember leave their dead. The body is carried past the trash heaps, a song is sung, and then the body is left to the process of decomposition. While it is believed that the Unknown Regions go on forever in all directions, they actually end 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 is the only known entrance to the city.