Building a Modern Nation in a Fantasy World
Chapter 82 82: Blast Furnace

The sound of hooves echoed across cobbled stone as Arthur's carriage rolled steadily through the heart of Iron Hearth, the anvil-beating soul of Keldoria's industrial frontier.

Peering out from the carriage window, Arthur observed the city unfold before him—raw, loud, and alive.

Iron Hearth wasn't polished like the capital. It didn't wear elegance or pageantry. It wore soot like armor and smelled of molten metal and smoke. The streets bustled with blacksmiths and miners, all hardened by fire and steel. Children with coal-smeared cheeks darted between carts, and the clang of hammer on iron was a constant rhythm, rising like a heartbeat from the forges.

Here, magic and muscle worked side by side. Artisans channeled mana through chisels, shaping enchanted tools, while other hauled carts of iron ore from the mines carved deep into the mountainside.

It was a place built by sweat and flame—a city that respected results over rank.

But Arthur wasn't here for the city.

As the carriage passed through the central district and began its journey toward the outskirts, the noise began to fade. The stone roads gave way to gravel paths, and the scent of the forges slowly vanished behind them.

The landscape changed.

Trees grew thicker, casting long shadows across the road. Wooden fences marked forgotten farmlands long since reclaimed by wilderness. The further they traveled, the quieter it became—until the only sound was the crunch of wheels and the gentle hum of wind through the pines.

This was intentional.

The blast furnace project had been kept completely secret—so much so that not even high ranking nobles such as Marquis knew what was being constructed. It had been placed far from the eyes and ears of the public, tucked behind natural hills and layers of forest to shield it from both rumor and spy.

As the carriage rounded a bend, a massive wooden palisade finally came into view. Watchtowers overlooked the perimeter, and guards clad in black-and-silver armor stood at attention, their spears crossed at the gate.

No banners. No signs.

Just a wall, a guarded gate, and secrets behind both.

The carriage came to a slow stop in front of the gate.

Arthur stepped down first, his cloak catching the wind. Behind him followed Ken, his silent, ever-watchful personal guard.

Arthur took in the sight before him. Though the structure inside was hidden by walls, he could feel it—the pulse of activity, the hum of mana, and the scent of smoke that always lingered where iron was born.

As Arthur approached the fortified gate, the guards stationed along the palisade snapped to attention. Their spears struck the ground in perfect unison, forming a silent corridor of respect.

But before Arthur could speak, a calm, composed voice called out from the side of the gate.

"You didn't need to come all the way here, Arthur. We've held things under control."

Arthur halted, recognizing the voice instantly.

He turned.

Standing beneath the watchtower was a young man clad in a dark mage's cloak reinforced with arcane thread. Silver sigils shimmered subtly across its lining, denoting both rank and magical discipline. His stance was upright, his expression firm and respectful.

"Aaron," Arthur said, nodding in acknowledgement. "I expected to find Loran first. Not you standing watch."

Aaron stepped forward and offered a respectful bow, hand briefly placed over his chest. "Loran is overseeing the final mana channeling for the inner chamber."

"I see," Arthur replied. "And your report?"

"Security is stable," Aaron answered immediately. "No intrusion attempts, magical anomalies, or suspicious movements detected within the perimeter. Patrol rotations are consistent, and the barriers are functioning as intended."

Arthur studied him for a moment. His brother's eyes were calm, but focused—like someone who took his duty seriously, not for praise, but because it mattered.

A small nod followed. "And Alice?"

"She's on perimeter patrol. We alternate based on shifts and sensitivity checks."

Arthur allowed himself a slight exhale.

Weeks earlier, as he quietly assembled a handpicked security team for the secret project in Iron Hearth, both Aaron and Alice had come to him—voluntarily.

Returning from the Royal Academy for the winter, the two of them had only recently completed their advanced training. While most nobles would've sought court appointments or soft military placements after such achievement, they had requested something else entirely.

"Assign us to where we're needed most," Aaron had said at the time, his voice clear and unwavering.

"We're trained. We're loyal. And we know what's at stake."

Arthur hadn't responded immediately then. But he remembered how he'd studied their expressions—neither hungry for glory nor seeking recognition. Only resolve.

He had agreed, because deep down, he knew the truth:

The spies would come.

Not now. Maybe not next week.

But once the world caught wind that Keldoria was building something—something hidden, heavily guarded, and tucked deep within the Iron Hearth mountains—foreign agents, spies, and opportunists would come like wolves drawn to blood.

They would come for sabotage.

They would come to steal.

They would come to understand what Keldoria was trying to change.

Arthur couldn't afford even a single mistake.

That was why he had assigned Aaron and Alice to this site. Not because they were family, but because they were reliable. Loyal. Rigorously trained. And above all, unshakable in their principles.

He needed more than just elite guards.

He needed people who wouldn't hesitate when it mattered most.

As the great gate closed behind them with a thud, Arthur, Aaron, and Ken stepped inside the hidden facility.

Arthur's boots crunched softly against the gravel path as the site came into view.

His eyes widened—not in surprise, but in quiet, measured satisfaction.

The blast furnace stood like a titan in the center of the construction yard nearly done with the construction, its massive stone frame towering nearly two stories high. The outer walls had been reinforced with heat-resistant bricks and alchemical binders, while scaffolding wrapped around the upper chimney, where a handful of workers were finalizing rune placements.

Further along the path, Arthur saw the wide wooden housing of a waterwheel, already turning in slow, steady rhythm—its gears transferring power to the mechanical bellows embedded at the lower chamber.

The air around the structure vibrated faintly with mana.

Arthur's gaze shifted to the glowing runic veins carved into the furnace's surface—mana channels—infused directly into the structure. These channels could be activated by a single mage as an alternative to the waterwheel, providing hot, controlled airflow into the combustion chamber.

A dual-source design.

That had been Arthur's innovation.

One source—mechanical, via the waterwheel-powered bellows.

The other—magical, via reinforced mana conduits etched into the furnace's very bones.

In a world where magic and machinery rarely cooperated, Arthur had made them complement each other.

That was what made this furnace revolutionary—not just that it produced steel faster, but that it did so flexibly, adapting to its environment, its operators, and its resources.

Aaron followed beside him in silence, allowing the king to take it all in.

Arthur's steps slowed as he reached the edge of the stone platform. From this vantage, he could see into the partially open inner chamber of the blast furnace. Its massive throat was lined with heat-tempered bricks and reinforced with binding clay mixed with powdered obsidian—designed to withstand the intense heat that would soon be unleashed.

Dozens of workers moved like a well-practiced machine. Teams hauled stone, realigned the leather bellows, checked the chimney vents, and carefully examined the rune lines that snaked across the furnace body. Each mana channel pulsed with a steady, faint blue—not active, but ready.

Near the base, one figure stood apart—his long apron covered in soot, a rolled scroll in one hand, and a chalk-covered measuring stick in the other.

Loran.

Arthur recognized him instantly—the best apprentice under Owen's tutelage. Young, sharp-eyed, and with a seriousness rare for his age,

Upon noticing the king, Loran quickly stepped down from the scaffolding and made his way to the main platform, brushing dust from his arms before dropping to one knee.

"Your Majesty," he said, head lowered. "I didn't expect you so soon."

Arthur stepped forward. "Neither did your crew, I'm sure. But I'm not here to disrupt—I'm here to inspect."

Loran rose, and Arthur's eyes scanned the blueprint rolled under his arm.

"How close are we?"

"Ninety-five percent, Your Majesty," Loran replied quickly. "We've completed the main structure, established the mana routing, and the bellows are functional. We're finishing the slag channels and sealing the upper hatch tonight. If no issues arise, the first ignition test can begin within four days."

Arthur looked up at the towering structure, expression unreadable.

"What challenges did you face with the dual system?"

Loran took a breath, ready to report.

"The waterwheel setup was straightforward. We used layered oak frames and treated the gearworks with resin to handle moisture. The challenge was balancing airflow—since the pressure required for a blast furnace is far greater than traditional forge bellows. We ended up using triple-linked bellows connected in sequence for a continuous push."

"And the mana circuit?" Arthur asked.

"More delicate," Loran admitted. "We had to re-etch the channels twice. The first rune pattern overheated and cracked the base stone during mana flow simulation. We corrected it by weaving the stabilizing sigils deeper and spacing out the amplification runes to prevent backflow."

Arthur gave a small nod of approval. "Good. It means you adapted. The blast furnace isn't just about generating high heat—it's about maintaining control. One surge, one moment of miscalculation, and the entire chamber could collapse from within."

Loran inclined his head respectfully. "That's why we ran three containment simulations before sealing the inner vents. We've accounted for every pressure point."

Before Arthur could respond, a clear voice called out from nearby.

"Sir Loran! I've finished the preparations of tasks you assigned me."

Arthur turned toward the voice, his gaze sharp and curious.

A young woman was approaching from the eastern scaffolding, her steps brisk and her expression focused. Her golden hair was tied back in a loose braid, and she wore a thick leather apron over her robes, smudged with charcoal and faint traces of mana dust.

Arthur's eyes narrowed slightly in recognition.