Prompt: Deep Castle

“Remind me again why we're out here?” Twilight said, pulling a few leaves from her hair as the two entered the clearing.

“It’s a surprise Twilight! I’ve been saving it for a special occasion, and your upcoming marriage is just the perfect occasion to pull it out!” Celestia replied, somehow free of tree debris and looking regal as ever, even when waltzing through the everfree on a Sunday afternoon. If Twilight didn’t know any better, she’d think this whole trip was just some elaborate pre-wedding prank pinkie and rainbow had managed to rope Celestia into. But Celestia looked too excited for that to be the case.

Twilight took a deep breath as the two finally pushed open the doors to the castle of the two sisters. Still in shambles, though rumor had it some noble was looking to make it a museum in the next few years.

She looked up at the shattered stained glass window and nodded to herself, this place would be good for showing off pre-banishement history.

“Come on twilight! This way.” Celestia passed through the doorway after her and walked over to one of the room twilight hadn’t yet been inside. She hadn’t exactly explored since her last visit. Her face scrunched up at the memory before she cast it aside. She was here for Celestia, maybe she would find something worth learning about along the way. A long lost book perhaps? She wouldn’t put it past her mentor to have something really special.

They got to an old looking bedroom, sheets tattered, but yellow enough to guess who used to bed here. It was smaller than she would have guessed.

Celestia walked up to the bed and grabbed the front with a hoof, lifting the whole thing to reveal a set a hidden stairs beneath the bedframe. The wooded frame had seen better days, and groaned upon being lifted. “Quickly now!”

She ducked under the edge before Celestia followed, a massive crash sounding out as the bed gave out.

“Is that going to be a problem?”

“Oh I’m sure you can lift a broken bed twilight. We will be fine. Come now, it’s quite a ways down from here.” she said starting on the surprisingly well preserved steps of the staircase.

Twilight looked down, but she couldn’t see the end of them, even with Celestias light spell.

“That’s a lot of stairs” she mumbled quietly as she followed Celestia down.

“The deeper the better!”

“Why?”

Celestia paused her walk for a moment, twilight nearly colliding with the royal rump before stopping herself.

She looked back over her shoulder with a surprisingly serious gaze.

“Are you aware of why we build this castle twilight?”

She thought about it for a while. She always loved showing off her expansive knowledge on all sorts of subjects, but after mentally tabulating all the books she could remember that went over the castle of the two sisters, she found herself drawing a blank. Some speculation of course, but nothing concrete. Even the speculation differed wildly.

She looked back to Celestia only to notice that they has both started walking again while she was thinking.

“I, I don’t know Princess. Why don’t I know? I’ve read all sorts of books on it, but none of them cover that particular aspect. Why? What was it built for?”

Celestia Hummed to herself. “I wasn’t sure if they wiped that part.” she paused. “It was originally built as a fortress. Unassailable by traditional means. But magic was wilder back then twilight. We didn’t understand the rules to the extend we do now. Few could even be formally taught it, most of us just went on instinct and let our cutie marks guide us. My sister and I needed somewhere we could be safe, in case some neighboring country elected a despot with a penchant for war. Since we weren’t sure what sort of spells would be in the armory of the enemy, we went a little overboard.”

She paused again, The silence of the stone staircase broken only by the clack of hooves on the solid granite steps.

“Be build down.” she finally concludes.

“Down? Why down? Wouldn’t it be better to have towers with mages, they could probably handle anything that was going around back then.”

“With what spells Twilight?”

“Shinys shield spell for one, maybe something with fire?”

“Shiny is a prodigy twilight, you know that. Even then he was working on thousands of ponies lives worth of gradual advances. We hardly knew how to make an autotelekenisis spell back then. Just enough to stop a throw rock automagically. Our offensive spells were little more than a raw outpouring of power, driven by instinct. Much like your fight with Tirek.”

“That was plenty powerful!”

“It was also one princess and two millennia of combined improvements combined. Sure one princess is powerful, but the pones often were not. We still had to leave to handle delegations once in a while. It was not always so easy.”

“But how does going down make any sense!”

“How much rock do you think is above us right now?” Celestia asked.

She looked up, momentarily forgetting about just how far down they were going.
45 minutes of travel, twenty ish steps per minute. How far down were they?

“A lot?” she ventured.

Celestia snorted in amusement. “Even if you calculated, you would be quite right. We are currently around a kilometer deep.

“What? How!”

“These paths were enchanted, they compress space just a bit.”

“You still haven’t told me why we’re going so deep.”

“It’s a bunker Twilight. A very old, still surprisingly secure bunker. This path was once the emergence exit for myself, to keep me safe in case something untoward happened up above.”

“But you’re the most powerful pony I know, Wouldn’t you be out fighting?”

“Contingencies twilight. We didn’t know if somepony could create a spell powerful enough to take us down quickly. This was originally only for use if something unprecedented was going to destroy the whole castle, leaving me and Luna only minutes to escape. Whatever it was might have still been able to get us if we were in line of sight, so we built down. Thankfully we never had to use it.”

The sound of her hoofsteps changes slightly and Twilight nearly tripped as the endless steps finally transitioned back into a short hallway.

“But that’s enough doom and gloom, this is a happy occasion!” Celestia stepped up to a stone door, and slotted her horn into it. Vibrate rainbow colors ran through a series of carvings before forming her cutie mark and settling into a yellow glow. After another second, a crack of what sounded like distant thunder boomed forth, and the horn slot spread slightly, forming either side of an incredibly thick door.

Celestia pushed it open with ease and a smile on her face, walking into room beyond.

“Ah this brings be back.” she said with a note of nostalgia in her voice.

“Why? What so special about an old bunker?”

“Well, I I'm honest twilight, I didn’t really put it to its proper use. I usually came here when I was looking to unwind after a long day. I couldn’t really have a proper night out on the town without everyone hemming and hawing over the local princess, so I set myself up a place down here instead. Hard for the nobles to find me here too, it was always such a relief to make it down the stairs at the end of the week.”

Twilight stepped in after Celestia and found a medium sized room with few furnishings, she could only imagine the difficulty of getting anything down here.

On the right wall was an old worn and gilded wooden bar, which caught her a bit by surprise. She hadn’t known Celestia to be much of a drinker.

At the back of the room was a very comfy looking bed, and on the left was a chair and couch next to an a positively ancient looking enchanted torch. As she took another few steps into the room, she caught what she was looking for on the left wall near the door. A bookshelf! So Celestia /Was/ giving her a book!

She sat their imagining which book it would be while pointedly keeping her eyes from the spines, lest she spoil the surprise early. All while Celestia had slipped behind the bar, bottles clinking with care as she dug around in the cabinets.

She emerged a minute later with an incredibly old, square brown bottle. “Yes! It’s still here!” she said in triumph.

Twilight gave her a confused look. Surely that wasn’t what she was after right? There were a whole bookshelf of goodies right there!

“What? I thought… but, books!” she said gesturing at the shelf lamely.

“Ha! You thought I was here for a book?”

“Well, yes! You know I love reading, and there's a whole shelf of ancient tombs right there!”

“Those were copied over years ago, at best you’ll find some dust first edition that’s been on the back shelves of the bookstores for millennia. Probably outdated too. Nothing special like this!” she said holding up the bottle.

“I didn’t even knew you drank!”

She gave a sheepish look. “Weeeeell. I don’t really anymore. Been too deep down that rabbit hole. But this is a special occasion, so I’m breaking out my personal stash.”

“What kind of alcohol could possibly be that impressive.”

“Zap apple Whiskey!”

Twilight face hooved.