The Dark Dimension is a fictional dimension filled with supernatural entities and currently only exists in the books. The name is generally used to indicate only the "City of Darkness".
To access the Dark Dimension from Earth, there must be access to gates called the "Kimon Gate" or more often, the "Demon Gate". One of these one, used by Elena, Damon, Bonnie and Meredith, is the Demon Gate of Sedona, which is located in a warehouse goods, which is run down in a cave outside of the city. On Earth, there are thousands of gates, which are located in the intersection between energy lines. Most of them were closed or have fallen into disuse after the arrival of Europeans and the disappearance of the Native Americans. The Demon Gate leads to the City of Darkness. The rulers of the Dark Dimension are the Guardians from the Celestial Court, which impose the order. The summit of power, however, is the Superior Court, which decides everything and has the power to restore, revive or kill.
The City of Darkness
The City of Darkness is located in the upper hemisphere of the Dark Dimension and is similar to a Limbo. The Sun is bigger than that of the Earth, has a dark color and it shows on the horizon in the middle to the East during both day and night, staining the atmosphere with red. The constellations that shine in the sky are different from those on Earth. The City of Darkness is governed by a dozen or fifteen castles and clans, each controlling the lands outside of the city, where they grow products and sell them. Vampires, for example, have a monopoly on the production of Clarion Loess Black Magic wine. They use the Lords of the slums to execute orders. Once, the city was ruled by the extravagant King Kelemen II. The noblest vampire living within the the City of Darkness is Princess Jessalyn D'Aubigne. Other important aristocrats, royalty and nobility living within the City of Darkness are Lady Fazina and Lady Bloddeuwedd. The latter, a brutal murderer, is killed by Elena, Bonnie and Meredith. After her death, her wealth will be distributed to the fifth area, which becomes a safer place thanks to its absence. In honor of the three girls (Elena, Bonnie and Meredith) who have destroyed her, many children and young people within the city changed their names to Aliana, Mardeth and Bonna.
The Kitsune, who live in the city, are responsible for the Demon Gate. Thanks to them, they pass easily from one world to another. The kitsune are located in the area further to the North, near the Grand Crocicchi.
Humans can only enter the city as a slave to a vampire, a demon, or a kitsune. To prove their condition, they must wear something on the wrists, bracelets which are similar to wrist cuffs. Their commerce is very common. After witnessing Elena protect a slave with her body from the master's whip, they develop leaks and rebellious slaves. There are also some people who don't become slaves of imperial property. The City is inhabited by a large number of Soul Shadows and some Orcs.
In the City of Darkness, electricity is non-available and owning mobile phones is considered to be a crime. The punishment for almost every crime within the city is torture followed by death. The prison of the city is the "Shi Shi no", a group of buildings where Stefan was locked and imprisoned in Shadow Souls. One can arrive to the prison through the kitsune district.
The Underworld is located in the lower hemisphere of the Dark Dimension. It corresponds with Hell. To access the underworld from the City of Darkness, one must go North, at the very extreme part of the Dark Dimension, where it is much colder. Only the power of telepathy works in this area. After the "Silver Lake of Death" (also known as "Mirror Lake"), inhabited by Kronosauruses, one reaches the hole leading to the Underworld.
The Underworld is a very cold, dark place made up of ice and snow and immersed in a perpetual twilight blue. There are three moons that rotate the sky. The first one is a huge, white and blue moon, the second one is a silver moon which is slightly smaller and placed in front of the first and the third and last moon is a tiny white moon which is in high orbit. The tiny moon has only 1/8 of the Earth's gravity. The Great Tree completely covers and holds the largest existing starry sphere, the Star Ball. The spear shaft and crooked branches of the tree strikes against those who try to steal its treasure (the Star Ball). After the branches strike someone, they begin to grow within the body of the one who was hit, slowly killing them. This happened to Damon in Midnight after Damon had saved Bonnie from falling to her death after she had fallen off the Great Tree to retrieve the Star Ball. The tree is eventually reduced to ashes after Elena uses her Wings of Destruction to destroy the tree.
The Underworld is ruled by the Hell Court. Its ambassador is Sage, an old friend of Damon, who holds the "Seven Treasures of Kitsune". It also serves as the Fortress of Hell.
The Celestial Court
The Celestial Court is to the South of the Dark Dimension, and corresponds with Heaven. It is also known by the name of The Other Side. Its architecture, predominantly white and blue, is full of minarets. From the Celestial Court are the Guardians, which are divided into three different types:
- The Blondes Guardians are guardians that have blond hair, blue eyes and a thin constitution. They oversee the City of Darkness. These guardians constantly think about duty and responsibility.
- The Brown Guardians are guardians that have black skin, curly hair and a lithe physique. They are the kindest of the Guardians and their purpose is to oversee the Underworld.
- The Red Guardians are guardians with short hair and almond green eyes. They are severe and intransigent. They are the typical Guardians of the Celestial Court.
The Guardians can recruit adepts among humans, though endowed with certain qualities. This is the case of Elena. When she was 14, while she was in the car with her parents, the Guardians are within a special kind of machine. This machine is invisible to the human eye. They set out to kill a young girl and bring them to the Celestial Court. Elena, however, was able to see the Guardians. She pointed to the Guardian's machine and her father, Thomas, ended up being distracted. This caused the tragic car accident that killed Elena's parents. The Celestial Court is ruled by a triumvirate, the Supreme Judges: Idola, a Red Guardian and the leader; Ryannen, a Blonde Guardian and Susurre, a Brown Guardian.
- The Dark Dimension seems to be based on the Divine Comedy of Dante Alighieri.
- In the TV series, the Dark Dimension does not appear, but a place called the Other Side is similar to the Underworld.
- Compared to the Dark Dimension, Earth only has the human world, which is equivalent to The City of Darkness.
- Some humans believe in Paradise/Heaven. It's where the essences/souls of living beings (humans, animals, etc.) can rest in peace and happiness after they die.
- In opposition of Heaven, it is a place called Hell. For humans that have died committing sins or acts of darkness and evil. Hell is a place of torture, darkness, despair, suffering and punishment. All beings who have committed atrocities and extremely violent, cruel, and sadistic actions will likely go to Hell after they die.