District 12 is the district that the most is known about throughout the whole series, other than possibly District 13. District 12 is the home district of main characters Katniss, Peeta and Haymitch, which is why it's the most well-known.
It's the coal district, and often considered the poored of all the districts. Before the 74th Hunger Games, there had only ever been two victors from District 12. They are at somewhat of a disadvantage because unlike every other district, the tributes from 12 know nothing about their trade. Mining doesn't begin until the age of 18, so the tributes don't know any of the helpful things that may help them in the games.
Before the Games begin the tributes are introduced to all if Panem riding on carraiges as part of opening procedure. Standard costumes for the coal district are very unattractive, as they always have to do with coal. One year Katniss reports that the District 12 tributes were stark naked and covered in coal. Cinna however takes a different route and focuses on the fire that burns coal. This could very well be the only successful costume choice in the history of District.
Coal mining is very dangerous, and there are explosions. Mr. Everdeen and Gale Hawthorne's dad both died in a mining explosion. This is one of the reasons the men of Disrict 12 don't begin mining until the age of 18.
Canaries are brought into the mines to warn the miners when breathable air runs out. The first warning is when the canary stops singing, and if no action is taken the canary dies. If still no action is taken the miners will die as well. In Catching Fire Katniss likens Wiress to a canary who warns them from danger. Indeed, when Wiress stops singing Katniss acts immediately without thinking, and likely saves at least one of her groups' lives. For Wiress had been killed from a sneak attack by the Careers, and only Katniss' quick actions save them.
 The Seam
 The Hob
The Hob is the black market of District 12 and was in an old warehouse. Gale and Katniss often sell their kills there, in exchange for essentials. Mr Everdeen used to go to the Hob with Katniss when she was young, and finally Katniss gained the courage to go the Hob with Gale. Though many of the officials knew about it, they never reported to the Capitol because their yearning for the illegal meat sold there outweighed their feeling of responsibility. However, it must have been discovered at some point, because the Hob went up in flames during Catching Fire.
 The Meadow
 The Forest
 Town Square
 Victor's Village
Like every district, District 12 has a Victor's Village, where victors of past Hunger Games and their families live. It is much more advanced than any other part of the district, and the houses even have telephones (Katniss comments that they are rather pointless, since the only people she knew with phones were Peeta and Haymitch, who lived right next door. She does begin to talk to Cinna regularly, however.) Before teh 74th Hunger Games Haymitch Abernathy is the only person who lives in the Victor's Village of District 12. However, after they win Peeta Mellark and Katniss Everdeen live there as well with their respective families. Katniss returns to the Victor's Village once she leaves the Capitol at the end of Mockingjay where Greasy Sae cares for her.
 Known Inhabitants
District 12 is destroyed in Catching Fire, so this is a list of people known to have lived there before the war, with a brief synopsis of their significance. Some people who are still alive no longer live there, such as Gale and Mrs Everdeen. This is a working alphabetical list.
- Darius - Frequented the Hob, flirted with Katniss. Became an avox after defending Gale during a whipping, and had to serve Katniss during the 3rd Quarter Quell
- Gale Hawthorne - Katniss' best friend and hunting parter, works in the coal mines, designs bombs with Beetee. Alive, but living in District 2
- Greasy Sae - The Seam. Worked at the Hob and would make stew from just about anything. Alive.
- Haymitch Abernathy - Victor's Village. Victor of the 2nd Quarter Quell, and originally male tribute in the 3rd Quarter Quell, but replaced by Peeta. Mentor every year for The Hunger Games since he won the 50th. Alive.
- Hazelle Hawthorne - Gale's mother. Helps Haymitch with his laundry and other chores during Catching Fire.
- Katniss Everdeen - Lives in the Seam, then Victors's Village. Victor of the 74th Hunger Games and female tribute in the 3rd Quarter Quell. Protagonist. Alive.
- Madge Undersee - Daughter of the mayor, and niece of Maysilee Donner. Gave Katniss her mockingjay pin token.
- Maysilee Donner - Merchant's daughter and childhood friend of Mrs Everdeen. Female tribute in the 2nd Quarter Quell. Died during that Quell.
- Mr. Everdeen - The Seam. Teaches Katniss to hunt, forage and sing. Dies in a mining accident when Katniss was 11.
- Mrs. Everdeen - Merchant's daughter, Seam, Victor's Village. Village healer and mother of Katniss and Prim. Alive, but living in another district.
- Peeta Mellark - Merchant's son, then lives in Victor's Village. Victor of the 74th Hunger Games, and male tribute in the 3rd Quarter Quell by volunteering. Alive.