@Nightweaver20xx  
In a few dozen years after hollowing it out, the oak would fit Twilight standing on two years. Give it a dozen centuries and you have something Golden Oaks sized.

@Nightweaver20xx
 
I’m pretty sure the Crystal Castle is in the spot the Golden Oaks Library used to be (neighbors be damned.) It would be poetic, at least.
 
I still think they should’ve given the CC a bigass veranda and had it regrow an exact copy of the GOL (sans contents).

@Nightweaver20xx  
Whatever.

@Background Pony #8739  
Fortunately trees are a renewable resource, so if the residents really wanted to, they could plant another oak there and in a few dozen years, hollow it out and put in windows and such and BAM, new Golden Oak Library.

Is it ever coming back?

@Neon97  
Yeah…

I really miss the library. It seemed so much cozier than the castle.

@Nightweaver20xx  
Emerald city?
 
But emerald palace just looks kind of evil overlordish in the middle of thatched roof houses.
 
But hey, it’s not like she forced them to make it, it kinda literally just grew, so…
 
Also there’s something amazing to the idea of a princess living in a humble, natural little home. Kind of beautifully egalitarian.
 

 
Would be nice to see her open her ground level at least up to the public more, though. I’ve always thought if I became super rich I’d like to share it somehow. Like have a grand, beautiful library, but somehow actually have it be a public library. Or maybe have some teaching center there. That would be awesome. Freaking awesome…
 
Maybe even have my own little private school or something in addition…
 
Heck, she used to actually live in a public library. It’d be just a little messed up for her to suddenly get a far larger library only to close her doors. We haven’t really seen solid proof one way or the other, though.

@Narlepoax III  
To be fair, the crystal castle was intended to look refined and regal, to act as a symbol in Ponyville of Twilight’s new status as a princess. It’s supposed to have been an upgrade to her living quarters, but in the end even the show’s characters (like Spike) make cracks about how large and confusing it is.

@Lucky Shot  
Twilight’s Library was designed by the season 1 design team. Faust and her team were given extreme amounts of creative freedom when first making the show; especially for Hasbro. That’s why she agreed to do it in the first place. There was almost certainly input from Hasbro, and probably changes to its design throughout its creation, but it was not designed solely by a toy designer. Let alone a toy marketer. That’s an important distinction. Making toys and selling toys are two very different jobs, and by and large, people have one or the other.
 
The crystal castle? Well, I don’t really know much about its design. I will say that it looks exactly like what a toy designer who was trying to make a newer, bigger, fancier, more expensive, palatial version of Twilight’s tree home would design.
 
If it wasn’t a toy maker, that is to say, if one or more designers on the show’s creative team genuinely had the idea by themselves, and created that ugly, crystalline, behemothic, eyesore, and truly thought that it was a great addition to the show, and would fit in perfectly…
 
Well, that would make me very sad.

@SeraphimDawn  
@Cirrus Light
 
Apparently Dave Dunnet did a lot of the concept art for Ponyville. From the first sketches it looks like what we have in the show, looking in “The Art of Equestria”.
 

 
“The Tree of Knowledge or Tree of Life is a common motif… …meant to represent connection between all forms of creation and understanding. It’s a fitting choice for a seeker of knowledge like Twilight Sparkle.”
 
“Twilight Sparkle’s domain reflects her varied interests in books, the stars, magic, and a quest for knowledge. The curved, organic interior of the tree suggests a mind with its many nooks, storage cubbies and stairways.”
 
That’s pretty much it on Golden Oaks. Heh, it doesn’t have any section on Twilight’s new castle, though it does have a behind the scenes section on the Tirek episode… :P
 
Also a quote from the production team that confirms - in case anyone still has doubts - that they really do think of what all the characters are thinking and feeling at each point, and animate them accordingly. You can really tell.
 

 
I could swear I remember seeing Lauren write about when she decided to have Twi live in a tree-house, though… Hmm, nope, can’t even find that on her deviantart. Odd.

@Cirrus Light  
Which begs me to wonder.  
Was Ponyville originally meant to look like a town of hollow tree houses like what Twilight’s library used to be?

@Lucky Shot  
I don’t think it was. I think I recall seeing sketches and such about how Faust designed it.
 
I’ll check my “Art of Equestria” book.

@Cirrus Light  

 
Aren’t trees often associated with evergrowing wisdom?  
Maybe that was why making the library into a tree made a lot of sense.

@Background Pony #1B67
 
Perhaps you’re not aware the library was also designed by a toy marketer… but yes, if bronies will accept one thing bad about Larson it is that he saddled us with Starlight.

@Amethyst_Crystal  
@Background Pony #1B67  
@PonyPon  
It will be very difficult for anything to ever match how cozy that home was…

You will be never be replaced.

to me the library was just the place where Twilight used to live

The magic of the show died with the library. It was so symbolic, new house of the protagonist, where all the adventures started and ended.
 
Now we have a plastic “castle” designed by toy marketer, and a new protagonist that is pretending to be the old one. And does it so badly even the writers of the show try to ignore her.

For Starlight, the castle is her only home.  
A magical mysterious otherworldly home.
 
But for all you wistful mourning nostalgia people,  
the first moments of seeing Golden Oaks in the show:  
 
Twilight Sparkle: “How did we get here so fast? This is where I’m staying while in Ponyville.”
 
@Nightweaver20xx  
The castle might be a living thing too. It did grow from a seed in the ground,  
and seems to have a strange connection to the tree of harmony beyond that,  
presumably via the cutie map.
 
@Lucky Shot  
Princess Ember really liked the castle, it was delicious.  
Also most of the ponies seem to be getting used to the place.
 
@Cirrus Light  
Thanks for sharing those really cool treehouse images!

@Lucky Shot
 
Apparently that kind of architecture actually exists…
 
 

 
Would love to see pics for this claim, though. Not even necessarily “pics or it didn’t happen”, just PICS NEEDED! Heh.
 
Here’s a really photoreal sorta take on it, though - in 3d, no less.
 
 

@Nightweaver20xx  
First and only good character death then? XD  
I Crei ;_;

Oh good. AJ’s parents are house-sitting Twilight’s tree. That’s awfully neighborly of them.

It reminds me of the starry skyline screensaver from the 90s.