It's like the backside of your worst nightmares. It's all blood and bone and darkness. Filled with the bodies and souls of all things hungry, sharp, and nasty.
Purgatory is a supernatural dimension created by God to contain his first and most dangerous beasts, the Leviathans. Over time, it became the destination of the souls of monsters. According to Bobby, it goes by many names, with "Purgatory" just being the most commonly known.
Appearance and CharacteristicsEdit
Purgatory appears to be an endless forest in an almost perpetual gloom or overcast. On two occasions, it was shown to be dark, as if during nighttime. Fog also naturally occurs in Purgatory. Despite its seemingly infinite size, there are certain locations and bodies of water that are fixed, and are used by monsters as reference points when trying to locate something or someone. While it seems devoid of tools and synthetic materials, there are enough basic objects (such as bones, rocks, and wood) found in it in order to form weapons of differing sizes and shapes. These weapons are crafted and utilized by Purgatory's inhabitants, presumably to fight stronger monsters they encounter. Strangely enough, there was also one occasion where a metal chain was featured in it.
According to a high-ranking Leviathan, Purgatory is a worse neighborhood than Hell.  Dean describes it as many different kinds of blood and gore. Despite this, he, as well as Benny, also describe it as being "pure," for yet to be disclosed reasons. This is most likely due to the fact that Purgatory is a place where one can either kill or be killed, relying on basic animal instincts, cut off from any outside interference or contact. This makes it distinct from Heaven and Hell, which function more like businesses.
Unlike other spiritual realms such as Heaven and Hell, Purgatory appears to be constant and corporeal, in that everything that exists there actually exists, as opposed to being mere imitations. This was proven by the fact Dean was able to take his blade out of Purgatory.
Foundation and Recent HistoryEdit
According to Death, when God realized his first beasts, the Leviathans, could threaten the survival of his other creations, he created Purgatory as a prison to isolate them.  In Purgatory, the Leviathans were kept to themselves and away from God's younger children and creations. Sometime after, Purgatory began to contain an ancient and powerful entity called Eve. Exactly how she came to exist and if she really originated in Purgatory or was simply sent or imprisoned there is unknown, although the Alpha Vampire has implied that she was related to the Leviathans in some way. Eve then gave life to her firstborns, the Alphas of different species of monsters. Eventually, Eve and her progeny became associated with Purgatory, and it became the destination of their souls when they died on the mortal plane. In Purgatory, the souls of the monsters are fated to prey on each other for eternity. It is currently unknown what happens to the souls of monsters if they die in Purgatory, though it is assumed they simply re-materialize after some time, thus repeating the process of preying upon each other forevermore.
There are estimated to be 30-40 million souls in Purgatory. These multitude of souls were sought by the King of Hell, Crowley, and the seraph Castiel, who both agreed to work together and use the power of the souls to secure their own respective positions after the aversion of the Apocalypse left a power vacuum.  The pair attempted to locate Purgatory by way of capturing and torturing different monsters, including the Alphas. This attracted the attention of a very angry Eve, who was at first content with the natural order, but was convinced that she needed to protect her children and her realm. She began to arrange for her children to create armies of their own and to summon her to Earth. This dragged Purgatory into a three-way power struggle, along with Heaven and Hell. Eve planned to turn all human souls into monsters in order to increase the power of her realm and to deplete Crowley of future resources. However, the struggle resulted into Eve's death. 
Castiel later successfully opened a portal to Purgatory and absorbed all the souls in there as well as the Leviathans. After his body began to deteriorate under the strain of the souls he had absorbed, he reopened the portal and returned all the souls to Purgatory, but some of the Leviathans clung onto Castiel's vessel and thus did not return to Purgatory.
After Dean killed the Leviathan leader Dick Roman with the Bone Of Righteous Mortal Washed In the Three Bloods of Fallen, he and Castiel were transported to Purgatory with Dick's essence when it returned there.  Castiel was forced to immediately abandon Dean as he feared that the more powerful monsters, including the Leviathans that were still in Purgatory, would come after him and he did not think Dean was safe.
Dean later teamed up with a vampire named Benny in order to find an "escape hatch" created by God in case humans ever got stuck in Purgatory. The two located Castiel and teamed up with him to escape, fighting off monsters and Leviathans that attacked them along the way. Eventually, they reached the portal which opened when it sensed Dean's presence. Dean absorbed Benny's soul into his arm. However, while Dean made it through the portal before it closed, Castiel, who may not have been able to make it out anyway as he is not human or a former human, stayed behind as he wished to do penance. Castiel was later rescued by an incursion of angels sent by Naomi which she said cost many angels their lives. 
When Sam asks for entry into Hell, the rogue Reaper Ajay takes Sam to Purgatory where there is a backdoor into Hell. Sam is able to travel to Hell and back through this door with Bobby Singer's soul, but as Ajay had been killed by Crowley, was stranded in Purgatory. Dean asked Benny to go into Purgatory to save them and he agreed, allowing Dean to kill him. When Benny's soul arrived in Purgatory, he lead Sam and Bobby to the portal, but opted to remain behind in order to hold off a group of vampires. Sam and Bobby escaped through the portal while Benny was seen being taken down by the three vampires. 
Access and LocationEdit
Crowley described Purgatory to be adjacent to hell, but implied it was quite difficult to access directly. He believed that the Alphas, and their mother Eve, knew how to locate it and therefore, create a passage to it. It would later be revealed that Crowley's intuition was literally true, although only reapers knew how to use the passage in between the two dimensions.
Although Purgatory functions as a prison and the final realm of monster souls, there were certain instances when its inhabitants were capable of escape, not unlike Demons escaping hell. Some spells could summon creatures out of it, for instance when H.P. Lovecraft and his friends successfully opened a passage to Purgatory and accidentally set loose one of its natives. It is implied that they also managed to glance through the passage as Lovecraft left in his novel a reference to creatures called the Old Ones. Monster souls may also escape if a human carries them out in their body and resurrects them on Earth.
Eve has, on at least one occasion (two occasions, if she originated in Purgatory), managed to cross over from Purgatory to Earth. She arranged for her Dragons to find a virgin girl as a vessel for her to manifest in on Earth, and they recited a spell at the mouth of a deep chamber with lava to summon her.  It is unknown how she achieved this the first time she walked the Earth 10,000 years ago, but it is presumed that she required the same spell and a similar vessel. All of these information were recorded on an ancient book kept by the dragons.
Another spell needed a lunar eclipse and blood from one of Purgatory's natives. This spell was so powerful it allowed the simultaneous release of all of Purgatory's souls. This spell was performed successfully by Castiel, who then absorbed the souls to increase his power. This spell could also be reversed in order to return the souls back into Purgatory.
Conversely, beings other than monsters may also find themselves transported to Purgatory; the Bone Of Righteous Mortal Washed In the Three Bloods of Fallen is shown and implied to send anyone near the Leviathan that the Bone is used on directly to Purgatory along with the Leviathan. When something other than a monster enters Purgatory, it seems that monsters that are there can sense the foreign beings, as word seemed to travel fast that a human and an angel had been sighted in Purgatory.
Because Purgatory was not designed to hold humans, there is a portal located in Purgatory which will become active when humans are near it, and will send any humans who enters it back to Earth in the Hundred-Mile Wilderness in Maine; it was indicated that the portal was created by God as an "escape hatch" in the event that any humans became trapped in Purgatory.
The vampire Benny knew of this portal and was convinced he could merge with the escaping human soul since he was once human himself. This was shown to be successful when Benny merged with Dean on his way out of Purgatory, and also resulted in the vampire's rebirth. This portal is located on a ridge and opens for a few minutes when it senses the presence of a nearby human soul, as shown when Dean approached it and was able to use it to escape. Sam later used it to escape with Bobby Singer's soul in the same manner.
Along a stream that runs through Purgatory, there are three trees that grow together between an arrangement of boulders that conceals a portal to Hell, a "backdoor" that rogue Reapers use to access it to take mortals and souls to and from Hell for a price. Only Reapers know about this, as even the King of Hell, and all of the demons are unaware of this. However, angels such as Naomi are aware of the existence of this portal.
It is unknown how the hierarchy in Purgatory is structured, or if there even is one. If present, it seems to be grossly fluid and not strict like that of Heaven, as the monsters in Purgatory seem to be largely on the run from each other, and were never shown to act in organized in groups or packs like they did on Earth. Only the Leviathans, some vampires, and seemingly the Gorilla-Wolves, were seen to behave with a group mentality so far. Prior to her death on Earth, Eve claimed dominion over all souls in Purgatory, so she is most likely the ruler of Purgatory.
Purgatory is the condition or process of purification or temporary punishment in which, it is believed, the souls of those who die in a state of grace are made ready for Heaven. This is a theological idea that has ancient roots and is well-attested in Catholic literature, while the poetic conception of purgatory as a geographically situated place is largely the creation of medieval Catholic piety and imagination.
- Season 6
- Season 7
- Season 8
- Even though every soul in Purgatory is deceased, they can still be "killed" as seen when Dean and Benny behead two vampires. Exactly what happens to the monsters that are killed in Purgatory is unknown. In Blood Brother, Castiel points out that this brings up a very good metaphysical question. It´s possible that dead monsters just regenerate themselves to hunt and eat other monsters just like tortured souls regenerated when they aren´t tortured in Hell.
- As of Taxi Driver, Sam, Dean, Castiel, and Bobby have all visited and escaped from Purgatory in addition to having been to both Heaven and Hell.
- ↑ Meet The New Boss
- ↑ Family Matters
- ↑ Like A Virgin
- ↑ Survival of the Fittest
- ↑ There Will Be Blood
- ↑ Meet The New Boss
- ↑ The Man Who Would Be King
- ↑ Mommy Dearest
- ↑ Survival of the Fittest
- ↑ A Little Slice of Kevin
- ↑ Taxi Driver
- ↑ Caged Heat
- ↑ Taxi Driver
- ↑ Let It Bleed
- ↑ Like A Virgin
- ↑ Taxi Driver
- ↑ Mommy Dearest