After trekking through the underground passage, we finally emerged into what felt like a vast, open expanse. There wasn’t enough light to see the full extent of the cavern yet, but the echoes of small stones I kicked across the floor suggested an immense volume of space.
In other words, this was it—the Great Cavern Yuta-san had mentioned, the one that had forced the resort development project to a screeching halt.
"First, let’s cast [Light] in all directions to see what we’re dealing with," Yuji suggested. "We can’t move around safely if we can’t see the whole picture."
"Got it."
"Right."
Following his lead, we began scattering [Light] orbs throughout the void.
As the number of glowing orbs grew, the true scale of the cavern slowly unveiled itself.
"Whoa... this is incredible."
"Yeah... I never dreamed it would be a find of this magnitude."
"I can certainly see why they had to reconsider the development plan... though it seems they were too late to save it," Hiiragi-san added.
The underground Great Cavern illuminated by our skills was far more massive than we had imagined. Based on Yuta-san's description, we had pictured something like a modest underground lake turned into a tourist attraction—still impressive, but manageable.
However, the Great Cavern before us was the kind of spectacular sight featured in nature documentaries, the kind that always has "majestic" or "primeval" in its title. The path from the entrance had been a slight downward slope, but I never expected a hidden cathedral like this, with a ceiling that soared twenty or thirty meters high.
"Even without a resort, this could have been a major tourist draw with just a little bit of work, couldn't it?"
"You're right," Yuji agreed. "Even without the hotel, it could have been a famous 'hidden gem' spot."
"Exactly," Hiiragi-san said. "A single major tourist attraction is usually enough to revitalize the surrounding area... It really just came down to terrible timing."
It was a tragedy that the cavern had derailed the original hotel design, but if a site of this caliber could have been commercialized, they surely would have recouped the costs of the delay. Unfortunately, the bubble burst before the plans could be adjusted. The development company went bankrupt, the local government withdrew, and the site was simply forgotten. It was a victim of circumstance.
The local government could have developed it as a revitalization project, but I suppose it was treated as a stigmatized property—a symbol of a failed investment.
"Still, with a space this large, the possibilities are endless," I noted.
"Definitely. We'd need to reinforce the walls, but as long as we don't do anything too flashy, we can get away with a lot here. And since it's underground, we don't have to worry about anyone peeking in."
"I agree," Hiiragi-san said. "If we renovate the cave while practicing our skills, it shouldn't take long at all. We can use our abilities to our hearts' content without worrying about prying eyes."
Our conversation was already shifting toward how we would terraform this Great Cavern into a functional base. It was true that having such a massive void underground made building a heavy structure like a resort hotel on the surface nearly impossible. But we didn't want to build a skyscraper; for our purposes, the lack of surface-level stability wasn't an issue at all.
In fact, building a massive structure in a remote area like this would only draw unwanted attention. It would ruin the benefit of having such a secluded piece of land.
"Oh, there's definitely seawater here. It's connected to the ocean, isn't it?"
"It is a cave right by the sea, after all... Look, there are even fish."
"That means we'll need to study how much the tide affects the water level," Hiiragi-san noted. "We can't develop the space properly until we know exactly how far the water rises."
Her concern was valid. Looking at the nearby walls, I could see algae growing a few inches above the current waterline, confirming that the level fluctuated with the tides.
While the regular daily changes might be manageable, the real question was how high the water rose during typhoons. Until we had that data, it would be wise not to leave anything valuable on the floor.
Beep!
As we were scouting, a high-pitched electronic chime rang out from my pocket—my phone timer. Our allotted time with Yuta-san was running out. In the silence of the underground, the sound echoed loudly.
I silenced the alarm and looked at the others. "Yuji, Hiiragi-san. It's almost time. Should we head back?"
"Ah, is it that time already? I was so focused I didn't even notice."
"Time really flies," Hiiragi-san said, looking disappointed. "I wanted to see what's further back. It looks like the cave continues quite a bit deeper."
Both of them looked genuinely regretful, and I'm sure my face mirrored theirs. We couldn't possibly explore every nook and cranny of this Great Cavern in such a short window.
It wasn't every day you got to see a sight like this, and honestly, I wanted to stay longer too... but Yuta-san was waiting and likely worried, so we had to be professional and stick to the limit.
"We can always come back if we're curious. Let's head up for today. Yuta-san is probably getting anxious."
"...Right."
"...I suppose."
Everyone was reluctant, but we ended our exploration and turned back to meet the deadline.
We made it back to the entrance just before the timer would have gone off. Yuta-san’s worried expression shifted to one of pure relief when he saw us.
"We're back. Sorry if we made you worry, Yuta-san."
"Ah, no, you're back before the deadline. I'm just glad to see everyone is safe."
"Haha, it's not like there are traps or monsters waiting to pounce on us down there," Yuji joked. "We weren't going to get hurt that easily. But man, that cavern was even more incredible than the stories suggested! I never imagined there was a place like that right under the Cape!"
As Yuji excitedly reported on our findings, Yuta-san looked a bit envious.
"I see. I'm glad you reached it safely. I've only ever seen the reference photos, so I didn't have a true sense of the scale."
"It was amazing! The ceiling had to be twenty or thirty meters high. Honestly, it's the kind of place that deserves a cover story in a travel magazine."
Yuji and Yuta-san continued their enthusiastic exchange across the gap where the old stairs used to be. Eventually, I tapped Yuji on the shoulder.
"Yuji. I hate to break up the party, but can we finish this once we're back on top? It's a bit awkward talking like this."
"Ah, my bad. You're right. It's better to talk on level ground. Yuta-san, if you'll excuse us..."
"Sorry, I wasn't thinking. I'll clear the entrance, just come on up....Do you need a rope or something?"
"We're fine," Yuji called back. "We're going to jump up, so please just stand back from the opening."
Following the warning, Yuta-san stepped away and disappeared from view.
"Alright, I'll go first."
"Don't jump too high and crack your head," I teased.
"I'm not that clumsy."
With a short run-up, Yuji leaped toward the entrance with an effortless stride. His body traced a graceful arc that defied gravity as he sailed through the opening.
Seriously, Yuji, you’re supposed to hit your head on the rim for a classic pratfall.
"Whoa, you really can clear that height in a single bound..."
"For an explorer with a decent level, this is a breeze," Yuji’s voice drifted back, a mix of casual indifference and a hint of pride. "Daiki, Hiiragi-san, you're up."
I could hear Yuta-san’s amazement from above. I suppose seeing a person jump five meters—the height of a third-story window—would be a shock to anyone.
Now that Yuji had paved the way, it was our turn.
"Hiiragi-san, who's next?"
"I'll go. Is that okay?"
"Sure. I'll follow as soon as you clear the entrance."
"Then I'll move out of the way once I land so we don't collide."
With the order set, Hiiragi-san took a light run-up and leaped just like Yuji had. Once I saw her disappear through the doorway, I followed suit.
"Phew. Glad to be out."
Once I cleared the entrance, I found the three of them watching me with strangely disappointed looks.
"Daiki, come on," Yuji said. "You were the closer, the big finale. Weren't you going to come up short or bump your head or something?"
"I don't need that kind of predictable routine... Wait, were you guys actually hoping for that?"
Realizing what those looks meant, I saw they’d been harboring the exact same hope I’d had for Yuji. I guess we were all cut from the same cloth.
"Anyway, is that it for our tour of the Great Cavern for today?"
"Ah, yes. Absolutely. Thank you for the incredible experience," Yuji said, turning to Yuta-san. "I see now why no one would want to build a hotel on top of that. Unless you designed it from the start with the cavern in mind, you'd be living with the constant risk of a catastrophic collapse."
"I agree," I added. "With a cavern of that size, it seems like a waste not to have turned it into a tourist attraction. It might not have been a massive hit, but you could expect a steady flow of visitors year-round."
"I think so too," Hiiragi-san said. "If it was featured in travel magazines or on TV, agencies would definitely include it in their tour packages. A majestic sight like that is rare."
As we praised the cavern, Yuta-san let out a small, regretful sigh and nodded.
"I suspect you're right. When it was first discovered, there were voices calling for it to be turned into a tourist resource. But when the government is involved, development is tied to the original plan. Unless something truly extraordinary happens, they tend to push the initial design through. This project was no different. Even when the resort had to be redesigned and delayed, they insisted on the original vision. There were even suggestions to just fill the cavern in. But the estimated cost of filling a void that size was astronomical. Then the bubble burst, the developers went bankrupt... and the project was scrapped entirely. The Great Cavern was forgotten, passed down as a 'bad debt' property that had bled the previous generation dry."
"I see... I guess no sane business would want to touch a site with that kind of reputation," I noted. "And the government isn't about to restart a project that failed so spectacularly once before."
I had wondered why such a goldmine was being left to rot, but it made sense. Everyone viewed it as a curse. A "let sleeping dogs lie" situation.
At least, for people looking to make a traditional profit.
"But in that case, this is perfect for us," I said. "A site that’s difficult to develop and has a bad reputation... it means other people will stay away."
"Exactly," Yuji added. "No one is going to complain if a group of youngsters like us buys or leases a piece of land that nobody else wants."
"And if there were already plans to fill the cavern in, I doubt anyone will mind if we tinker with the interior a bit," Hiiragi-san said. "Naturally, we'll get the proper permits for any major work."
Hearing our words, Yuta-san seemed to catch our drift and offered a small smile. He straightened his posture, slipping back into his professional salesman persona.
"I'm glad to hear it. It seems the property I've shown you today is to your liking?"
"Yes," Yuji replied firmly. "It's a very intriguing property. We'd definitely like to hear the details."
"Very well. Let’s head back to the office so I can give you a thorough briefing."
"We look forward to it."
Yuji and Yuta-san exchanged grins and a firm handshake.
Yeah, as long as the terms were right, we had found a winner. We’d stumbled onto a prime piece of real estate and were already planning our next move.