The tree itself appears to be a species of willow, most likely a weeping willow. It has a main canopy and three smaller canopies which branch out from the center. The canopies are connected by narrow wooden bridges. Built into the base of the tree is a wooden shack from which the rooms inside the canopy can be accessed. Various decorations, including windows, flags, and chimneys, can be seen sticking out of the canopy.
After the events of "Little Brother", the Tree Fort blossomed and became covered in many tiny pink flowers.
In "The Vault", it was revealed that the Tree Fort was originally a sapling near the Candy Kingdom. After being mutated and disfigured by the radioactive river that surrounded the kingdom at the time, Shoko died under the sapling along with Princess Bubblegum's amulet.
Once the tree had grown, it was converted into a house. Various residents began living in its walls. Marceline and Ash moved in together, as seen in "Memory of a Memory", until their later breakup. Marceline retained ownership of the house at this point, and carved an "M" into the bark to signify this, but eventually moved out.
Finn and Jake moved into the Tree Fort at some point before the start of the series, even though they did not officially own it as revealed in "Evicted!" Marceline let them continue living there, but in "Ocarina" she traded Kim Kil Whan the deed in exchange for a new, large, multi-necked guitar. In the same episode, it was traded to Jake in exchange for a broken ocarina, as a symbol of his "father love", finally passing legal ownership to Finn and Jake.
After Flame Princess destroys the Ice Kingdom in "Frost & Fire," Ice King temporarily moved into the Tree Fort in "Earth & Water," but left in "Play Date" after he reveals that the Ice Kingdom had actually been rebuilt for weeks.
In the distant future (around 1000 years), as seen in "Lemonhope Part 2", the tree grows much taller, reaching far up into the clouds.
The entry to the tree fort is the storage site for the treasure Finn and Jake collect on their many adventures. Without all the heaps of gold, the entrance is a simple empty room with a wood front door on one end, and a ladder leading up into the hollow trunk of the tree on the other.
The entrance can best be seen in the episode "Video Makers" when Finn is looking for a video camera. It can also be seen in "Play Date" when Finn and Jake dump their treasure in the room and later at the end when Ice King and Abracadaniel summon Kee-Oth the demon.
In "Furniture & Meat," Finn and Jake decide to spend all of the treasure in the treasure room. Some of the gold was spent by them, and the rest was melted by Wildberry Princess. The treasure room is now completely barren of any treasure, with the exception of a single gold coin found by Finn at the end of the episode. In addition, the Ancient Psychic Tandem War Elephant occasionally resides there. Prior to clearing their treasure, the entrance of the Tree Fort included old TVs, VHS tapes, a unicycle, lots of gold, a Nintendo Entertainment System (NES) complete with several games, a rubber duck float, a skull stabbed with a sword and a few other unique and/or unusual things the duo picked up during their adventures. However as of "The More You Moe, The Moe You Know (Part I)" there aooears to a few piles of treasure and as of "Don't Look" there appears to be a lot of treasure and and artifacts once again.
It appears to be completely hollow. The entire interior of the tree trunk is covered in boards. The hollow trunk is completely filled with treasure. There is an intricate web of ladders to get around it. One of the ladders leads up into the canopy where the living room is located.
The inside of the trunk is very rarely shown as it is empty and relatively insignificant. Aside from that, it was shown in "Guardians of Sunshine" when the whole front of the tree was blown out.
The living room is furnished with a brown colored couch, a little table they put BMO on when they play video games, (as seen in "Business Time") several long tables, and a large monster-skin rug. In the corner, there is an old phonograph and what looks like a wood burning stove with a pile of kindling next to it. This is the room where Finn and Jake typically spend their leisure time, usually doing activities such as watching movies or playing video games on BMO. There is a clock on the wall that says, "Finn and Jake - Timeless." The living room is next to the kitchen.Above the couch there is a picture that seems to be a nude lady except the picture is torn over it to cover up the areas children would not want to see,as said in the paragraph below.
There appear to be two living rooms: one with a long brown couch, round red couch, and cooler; and another with a purple chair and monster skin rug. The rug room is located one floor above the couch room. The 'couch room' may be the kitchen, as it contains the semi-nude painting referred to in the Kitchen and Trivia sections below - see: Painting in Living room.
The bedroom is over the living room and is accessed by a ladder made of planks nailed into the Tree Fort tree's trunk. The jaws of a very large shark are hung on the wall over his bed and a spiked mace hangs from the ceiling. The skin of some unknown six-armed beast lies on the floor as a rug. A large tree limb growing through the room has an old battered desk on it. There is an insect in a jar under the desk, as seen in "Her Parents." There is an empty room behind the giant root, as seen in "Rainy Day Daydream." The room holds a closet, a book shelf, a window, a picture of a ninja, and a weapon stuck in the ground. In the episode "Holly Jolly Secrets Part II," the bedroom is completely different from the bedroom in the other episodes. Their room in this episode is much larger, more bare as the root next to the bed is gone, and it has a fireplace. There are also many peculiar looking television screens that are on the walls that can be found throughout the house. So far the small TV's have found no use in the series other than acting as potentially noticeable decor.
On Finn's bed is his Eskimo-style sleeping bag on top of many pelts of various evil-looking furred and scaled monsters. Finn dislikes worms crawling on his bed, as he demonstrates when he throws a book (the Enchiridion) at a worm and yells, "No worms on the bed!" in "Evicted!" Next to the bed is an end table with what seems to be a mug and a rusted muffler being used as a candle holder.
Jake sleeps in an open drawer of a cabinet, which also holds his viola, a picture of Lady Rainicorn, books, bones, and some of his other personal possessions such as a mug which looks to hold milk, ties, and a locket of a "J" covered with jewels.
A small cave/megalithic structure is built into the tree fort on its back side. It appears to be where Finn and Jake keeps their tools and equipment that require maintenance; it is here that Finn gains the material and equipment that he uses for creating Neptr in "What is Life?" This location is also used in "Hot to the Touch" for assembling fireproof suits.
The attic is seen in "Rainy Day Daydream." There are the initials "AT" (that presumably stand for Adventure Time) carved into the tree, and a rug with various items such as candy and books. There is also a picture of Lady Rainicorn near the rug. It seems to be very dirty, and it is presumed that nobody cleans it. Seemingly, the only way to get into the attic is from the weapon room (the branch directly below) by climbing into a bucket and using a pulley system to haul the person or objects up. Otherwise, one must use the bridge that is connected to the living room will grant access to the attic. It seems to be an abandoned area since there are only a few items that are useful. However, it appears that Finn and Jake do use it sometimes. It also appears in "Go With Me" when Finn talks to Marceline about Princess Bubblegum not liking him.
The yard has several features including plants, a pond (which is sometimes shown with nymphs, and currently is the residence of Football), a well, a yurt (the round hut structure), a mechanical device that might be an electrical generator, and a vegetable garden in the back. The well does not have water in it. Instead, it is the entrance to the Beneathaverse where the Gnomes rule.
The Den is a small room connected with the Living Room presumably used for miscellaneous purposes. It has a large gauntlet, a small gauntlet, and a small bomb that resembles a nuclear weapon. It has appeared in "Rainy Day Daydream" and in "Beyond this Earthly Realm." The room may also appear in "Holly Jolly Secrets Part II" when the Ice King breaks in, as the green divan is seen to the left of the chimney. It also has a bookcase, a chair with a pillow, and a desk with a notebook near the large gauntlet.
Seen mostly in the episode "Slow Love," Finn and Jake keep a boat as a type of look out view at the very top of a branch at the top of their Tree Fort. It has an umbrella, a dining table and four chairs, a lamp, a carpet, a yellow-red telescope (sometimes pointed towards the Candy Kingdom as seen in the game "Legends of Ooo"), a tripod, and other small objects in it. It also appears in "Power Animal" at the roof party and "Dad's Dungeon" when Jake turned into different things for Finn and BMO.
The top of the tree that the tree house is built on.
Although the roof appears to be the top of the tree's canopy, it is a solid surface. Therefore, it has been used for parties and star watching as seen in "Power Animal" and "Incendium" as well as a solid surface for Marceline in "Marceline's Closet," towards the end of the episode, when Marceline is trying to imitate an owl sound, while lying there. She was spying on Finn and Jake, and was seen right after Jake sees Finn (vice versa) and the duo scream.
This room was seen in only a handful of episodes. It is possibly located near the bedroom. It consists of a wooden bathtub/shower, a mirror, and a toilet. In "Marceline's Closet," it shows it not having a door, but it has animal skins hung up in a doorway. This episode shows it being near their bedroom. In "Slow Love," it shows the doorway with animal skins if you look through the window, this may prove it is located in their living room. In "Five Short Graybles," it has a door and it is located in the hollow log in their kitchen. BMO uses this room in the episode to interact with Football, while in "Davey," it is the place where Finn had cut his hair.
Seen in "Rainy Day Daydream," this is where it links the "attic," and the living room. There are two bridges on the fort as seen in zoom-outs of the tree fort.
This was seen in many episodes such as "Beautopia," "Conquest of Cuteness," and also in the game, Legends of Ooo. It has a couch, a table, a picture (see 'Trivia' section bullet point 3), a stove, and other kitchen appliances. The room must be on the ground level since Susan was standing on solid grass when she broke through the wall. This room is also referred to as a second living room, see "Living room" section above, and the house breakdown diagram in the gallery. Underneath the floorboards lie Shoko's remains.Jake loves the kitchen as he is always making food such as:Breakfast,dinner,lunch and his special sandwiches.
Various creatures live inside the walls, as seen in the episode "Shh!," such as a humanoid male with a typewriter, a rather cartoonish-looking spider, and six mice with beds in various colors. There is also a cat sarcophagus surrounded by hanging decorations and small pyramids. In the episode "Little Brother", it was seen that there are more various creatures and places in the wall, such as the Rat King and Dewpia, when Shelby's Little Brother Kent had an adventure inside the wall.
Full list of residents
Inhabitants of the wall
- Man in Wall
- Ancient Psychic Tandem War Elephant
- Ice King (From "Earth & Water" to "Play Date")
- Rat King
- According to Finn, Science Cat and Shark appear near the Tree Fort at 4:00 p.m. every day, although this has only occurs once in an episode.
- Shoko (otherwise known as the Ghost Lady or The Green Lady, which is also one of Finn's past life) died next to the Tree Fort when it was a little sapling. Her skeleton lies underneath to this day.
- On a clock hanging in their tree fort, there's a picture of Finn and Jake on the hour and minute hands (respectively), surrounded by the words "Finn and Jake--Timeless."
- On the wall above the couch in the kitchen/lower living room, there is a ripped picture of a seemingly naked woman. However, according to Natasha Allegri, "It's not a naked woman, it's a woman in a crappy snapped bikini."
- Finn and Jake keep piles of gold coins, gems, and other treasures in the entryway to their house; though, in "Wizard," when Finn thought he had to pay for the last magic lesson, he said, "You can't do this to me man, I got no money!" though it is presumed that he didn't bring any money with him at the moment.
- The den/weapons room contains a full suit of body armor, but in "Blood Under the Skin" Finn ignores this and goes to Choose Goose in search of armor.
- In the episodes "Slow Love" and "Guardians of Sunshine," the Tree Fort is nearly destroyed but then rebuilt.
- The tree fort as seen in "Business Time" is completely different from the regular build in later episodes.
- The tree fort is an area in the game Project Exonaut.
- It is shown in "Conquest of Cuteness" that there is a network of small tunnels with openings which the Cuties used to their advantage to quickly move around and escape from the fort.
- In "Holly Jolly Secrets Part II," when the Ice King breaks in through the chimney, there is a picture of a humanoid figure wearing a uniform like the ones from Star Trek.
- In the back of the Tree Fort is a cloud, somehow tied to several rain barrels, as seen in "What Was Missing."
- In "Holly Jolly Secrets Part II," there is a briefly seen picture of what looks like a human hand making the peace sign.
- There is a sign saying "God Bless This House."
- Besides gold, the treasure room has pre-war items in it.
- In the Cartoon Network game Splashback, the Tree Fort is one of the backgrounds used in the game.
- In the unused storyboard, "Brothers in Insomnia," Finn cuts down a large branch on the Tree Fort (the one on the left).