Timmy's Treehouse

Timmy's Treehouse is a clubhouse built in a tree in the Turner family's backyard.

Information
The wooden structure is built on top of a tree in Timmy's backyard. Here is where he, Chester, A.J., and sometimes Sanjay and Elmer hang out. Tootie sometimes comes around wanting to play with them, but they will not let her up because she is a girl. Timmy's fairies sometimes use their magic to change the place around and make it more interesting.

Background
In the episode "Boy Toy", Timmy, Chester, and A.J. fled inside the treehouse, which they called their "Anti-Girl Fortress", when Tootie wanted to play with them. Cosmo and Wanda changed it into a metallic room with a chair and screens like the bridge of a spaceship, and Timmy and his friends launched magic water balloons at Tootie. She was eventually able to get inside anyway, and took doll-form Cosmo and Wanda to her house to lure Timmy there. Timmy later returned to the treehouse after retrieving the dolls, where Tootie was outside waiting to throw a water balloon at him.

Timmy also used his his tree house as a radio broadcasting station in "MicroPhony", encouraging adults to take their children to the beach with them instead of hiring Vicky to babysit. Eventually, Vicky caught onto Timmy by following a helicopter-form Cosmo all the way back to the treehouse, where she barged in and tied Timmy up with wires. She then used a Magic Microphone Timmy had wished up to disguise her voice as Double T (Timmy's radio persona), and promptly insulted all the adults in Dimmsdale. An angry mob formed outside the treehouse, but Timmy's friends and the other neighborhood kids rushed to his defense.

On the premiere night of "Crash Nebula vs Crimson Chin" in the episode "Sleep Over and Over", Timmy hosts a sleepover at his treehouse with Chester and A.J., but a disagreement other which is the better superhero results in a fight between Timmy's two best friends, who each decide to have sleepovers at their own places instead, while simultaneously inviting Timmy to their places. After bringing his friends back together by having them rescue him from junkyard dogs, Timmy successfully hosts the sleepover at his treehouse even though they missed the premiere of the special, that is until the junkyard dogs find them and get inside Timmy's treehouse.

In the episode "Timmy's 2-D House of Horror", the treehouse was the location from where Timmy wished a movie called The Haunted Volcano to be more realistic, causing a lava flow to burst from the treehouse and land on Vicky's House.

Timmy tried to hide in the treehouse in "Dread 'N' Breakfast" after his home had been turned into a bed and breakfast, and several of Timmy's adversaries showed up. Timmy planned to hide in the treehouse until they went away, but Tootie found him and ripped through the roof to get him. Timmy manages to escape her using a zip-line from the treehouse.

Trivia

 * According to a gag in the episode "Boy Toy"'s script, on top of not allowing girls, they also apparently do not allow kids whose names sound like bodily noises )
 * The treehouse interior changing into the "Anti-Girl Fortress" resembles the Starship Enterprise from Star Trek. Timmy also calls the water balloons they shoot at Tootie "phasors", a term for laser guns in Star Trek.
 * On "School's Out!: The Musical", the treehouse turns into the White House.