Hell
2.14 Born Under a Bad Sign
Ruby: Actually, they got it pretty right, except for all the custom leather.
3.09 Malleus Maleficarum.Hell in Supernatural verse is the place of punishment and pain in the afterlife. Humans who sell their souls to a Crossroads Demon or other demon go to Hell. It is unclear how or if other humans end up there. Human souls who are sent to Hell are tormented until their humanity is stripped away and they become demons (3.09 Malleus Maleficarum). Even demons find residing in Hell a torment.
Alastair tortured Dean and John Winchester while they were in Hell, and they saw Alastair's true demonic form while there. According to Alastair, John Winchester spent 100 years on his rack. He escaped through the Devil's Gate in Wyoming during the events of 2.22 All Hell Breaks Loose: Part Two.
Dean spends four months of Earth time in Hell, but he reports that time passes differently there: for him it is more like forty years (4.10 Heaven And Hell). This makes 3 days on earth roughly equivalent to a year in hell. During his time in Hell, Dean is tortured and each 'day' his wounds are healed so that the torture can begin again. At the end of each session, Alastair offers to stop the torment, if Dean agrees to become a torturer of souls himself. After 'thirty years' in hell (or 3 months on Earth) Dean accepts the offer and starts torturing souls. This broke the first of The 66 Seals, starting the process to free Lucifer. Alastair also made the same offer to John Winchester that he made to Dean, but John held out until his escape.
Castiel reports that angels laid siege to Hell to rescue Dean before he broke the first seal, but did not reach him in time. Eventually it is Castiel who rescues him.
Some demons appear to be able to move freely between Hell and the mortal realm, e.g. Alastair. Others are trapped and can only escape through portals such as Devil's gates.
When a demon is exorcised, it leaves its meatsuit and returns to Hell, whereas the Colt and Ruby's Knife can kill a demon, destroying it for good. With his psychic ability Sam exorcises, and eventually kills, demons.
Lucifer is imprisoned separately from demons, in what is called Lucifer's Cage, and is held captive by the seals.
It appears that hell is split up into sections. In a recent interview with Sera Gamble it is revealed that Lucifer's Cage is in fact the 9th circle of Hell. This section of hell is the worst and according to Sera Gamble not even Archangels can escape without a door way being opened from the outside: eg The 66 Seals or Horsemen's Rings. Other evidence is when Azazel contacts Lucifer and states that Lilith is "trapped deep, deep within the pit".4.22 Lucifer Rising
