Bart's treehouse

Bart's treehouse is the treehouse owned by Bart Simpson that resides in the back garden of 742 Evergreen Terrace. Bart and his friends usually read comics in the treehouse.

History
Bart often comes to the treehouse with friends, mainly Milhouse.

Milhouse once ran away from filming and hid in the treehouse.

It once housed a casino.

When Bart and his friends were trying to listen in on Lisa's tea party with her friends, Lisa saw the paper cup which the boys were listening from, and pulled it. Then the boys started pulling it, and it turned into a tug of war, until Bart's treehouse fell apart due to the pressure of Lisa's pulling on the tree. Then, after Homer's disastrous attempt and getting a plan for the treehouse (which turned out to be something created by a person Homer doesn't even know) and chopping down trees in the forest for wood, Marge called on the Amish. The Amish put together the treehouse pretty quickly, but the grand opening turned into a disaster when Homer switched the electricity on (put together by the Amish) and the electric wire exploded and the whole treehouse was set alight. Homer got trapped in the treehouse, but when Santa's Little Helper went to "save" him, he dragged out the turkey instead. Snowball II ran up, and Homer, unconscious on the floorboards, was woken up (or rather scratched on the chest) by the cat, and was lead out of the window safely.

Bart once held a Playdude party in his treehouse, inviting many friends over to it.

Mario also used Bart's treehouse to avoid the trash cans been thrown by Homer after he annoyed him but he is struck by one.

It was destroyed a second time, before being rebuilt, along with the Simpsons' house.

Once, when Bart escaped from Jimbo after he discovered that Shauna, his girlfriend, was cheating on him with Bart, he hid from the bullies in the treehouse with Shauna.

Wayne Slater also used Bart's treehouse where he sleep and sleeptalking.

Lisa also paces sadly around Bart's treehouse.

Snake Jailbird once hid in there when he was on the run from the law.

Description
It is a small house made of wood with a ladder leading up to it and a secret entrance in the floor. It's got a couple of windows as well as the door. The interior of the treehouse often changes, usually it contains only rudimentary furniture, but other times extravagant furnishings.

Trivia

 * In different episodes the treehouse has been seen in different locations of the backyard.
 * After building the treehouse in The Simpsons: Tapped Out you unlock (and watch) the 3rd cut-scene in which Homer collects the money and xp dropped by the treehouse while going round Bart who fell out the tree after it was built.