Golden Oak Library

Golden Oak Library is a stocky hollowed-out tree and the home of Twilight Sparkle, Spike, and Owlowiscious in seasons one through four. In Twilight's Kingdom - Part 2, the aboveground portion of it is destroyed by Lord Tirek and Princess Twilight subsequently gains her own castle as part of her Friendship Rainbow Kingdom. The main reading room is on the ground floor, while the bedroom is on the second floor. There is also a basement where Twilight performs her measurements on Pinkie Pie in Feeling Pinkie Keen. It is also called (the) Golden Oaks Library or Golden Eagle Library in some merchandise, Books and Branches Library at a former Hub website, and Twilight's Library in Gameloft's mobile game.

The tree has a beehive hanging from a branch, a candlestick sign on the front door (sometimes an actual candlestick figure, depending on individual animation errors), a sign of an open book outside the door, and two balconies, one of which has a telescope.

According to Lauren Faust, Golden Oak Library was originally called "The Tree of Knowing".

Season one
In Friendship is Magic, part 1, Princess Celestia sends Twilight to Ponyville to supervise the Summer Sun Celebration preparations. She was supposed to stay in the library during her stay in Ponyville. The library is protected from lightning by a magical lightning rod as mentioned by Twilight in Look Before You Sleep. During the thunderstorm, Twilight has a slumber party with Applejack and Rarity and during the end of the episode, a tree falls into the bedroom through the window. In Swarm of the Century, Twilight wakes up in the morning to find the library infested with parasprites. In Sonic Rainboom, Rainbow Dash crashes into the library and knocks all the books off the shelves, making Rarity, Twilight, Pinkie Pie and Applejack organize them again.

Season two
The library also has every Daring Do book in the series, as mentioned in Read it and Weep.

In times of difficulty, Twilight often turns to her vast library to find answers. For example, in The Cutie Pox, Twilight pulls out a book called Perplexing Pony Plagues to diagnose Apple Bloom's case of "Cutie Pox".

In Ponyville Confidential, the Cutie Mark Crusaders attempt to find a way out of their current situation. After they try asking Rainbow Dash and Fluttershy, the trio go to the library in hope of getting help from Twilight. Spike yells at them that Twilight, anticipating their arrival, had set up a magic barrier.

Season three
In The Crystal Empire - Part 1, Twilight magically rips the entire tree out of the ground, exposing its roots. When Twilight and Spike are searching for a way to eradicate the Pinkie Pie clones in Too Many Pinkie Pies, Spike discovers a horseshoe-shaped button hidden in the back of a bookshelf. Upon pressing it, a secret compartment containing the desired book is revealed.

In Magic Duel, Trixie uses her magic to flip the library upside down and shake books from it to the ground to persuade Twilight to have a duel with her.

Season four
In Princess Twilight Sparkle - Part 1, Rarity mentions that after the Summer Sun Celebration, she and Twilight have a meeting scheduled to redecorate Twilight's Loft now that she's a princess.

Her house also appears in Castle Mane-ia, Daring Don't, Power Ponies, Bats!, Pinkie Apple Pie, Three's A Crowd, Twilight Time, Maud Pie, Testing Testing 1, 2, 3, and Inspiration Manifestation.

In Twilight's Kingdom - Part 2, most of the library is destroyed by Lord Tirek when he attacks it in his attempt to take the princesses' combined Alicorn magic from Twilight. Twilight barely escapes with Owlowiscious before Tirek's attack razes the library.

Season five
According to a conversation with Hasbro Studios vice president Mike Vogel, "a whole episode in Season 5" is "devote[d]" to answering the question of whether Twilight is "still going to use/live in her library".

In one of the shots of the season 5 trailer, Twilight and Spike visit the ruins of what once was the library to pay their respects.

Other depictions
In gaming, the library serves as the setting for the Discover the Difference game. In Gameloft's mobile game, it is called "Twilight's Library". In Treehouse TV's Friendship Express Train Contest, the library is called "Golden Oaks Library". It is also featured in Electronic Arts' Hasbro iOS app Monopoly Hotels under the same name. The Club Hub area of The Hub's website calls it the "Books and Branches Library."

In Sparkle World magazine, the Golden Oak Library is featured in the stories Christmas at Canterlot!, Spooky Slumber Party!, and Winter Wonderland!

Merchandise
The Golden Oak Library is featured and mentioned in Enterplay's trading card game and collectible card game Cards #7, #78, and #ƒ25 of the trading card game refer to it as "Golden Oaks Library".

In chapter books and storybooks by Little, Brown and Company, the library appears or is mentioned in Twilight Sparkle and the Crystal Heart Spell, Welcome to Equestria!, Under the Sparkling Sea, The Elements of Harmony, Pinkie Pie and the Rockin' Ponypalooza Party!, Welcome to the Crystal Empire!, and Rainbow Dash and the Daring Do Double Dare. It is also featured in the Twilight Sparkle Animated Storyteller-bundled Welcome to Ponyville and Phidal Publishing's Stuck On Stories and Golden Oak Library.

The library is featured in an 80-page manga released by Shogakukan on October 16, 2014. In one of the manga's stories, the library, sentient and capable of speech, falls in love with another talking tree.

In the Swedish and German versions of My Little Pony: My Sound Book, the Golden Oak Library is featured; the English version refers to it the "Golden Eagle Library".

Quotes
"まあ、なんてすてきなえだぶりの方♡ わたしライブラリーのラリーですの."

- My Little Pony Comic & Quiz magazine