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Anubet, the Iron Gate of the North, is the empire's great metal bulwark, a city built for one purpose: holding the line against everything that lives beyond it. Its walls rise a hundred meters, forged from a pure iron that hasn't rusted once in four thousand years of the empire's history, because the iron itself was never truly ordinary to begin with. Both it and the walls raised from it were a gift from the Emperor himself—some say given outright, others say raised by his own hand—and that origin shows in small, uncanny ways. The metal never rusts, and even under the region's blistering sun it stays cool to the touch, never heating the way iron should.
It doesn't expand or contract with temperature the way ordinary metal does either, holding its exact shape and dimension through the desert's brutal day-night swing and the hottest forge-season alike. Left alone, the metal is also self-repairing—scars, dents, and pitting from centuries of siege eventually smooth themselves over given enough time. The one exception is anything driven into it and left there; a door, a window, an anchoring spike, anything fixed into the metal on purpose stays exactly as fixed, with no healing around or against it. Only once it's removed does the metal finally close back over the gap, reshaping itself seamlessly as if nothing had ever been set into it at all.
The city's church has taken this as its charge, presiding over rites said to be what actually maintains the walls' unnatural properties. Whether that's genuine divine upkeep or simply a story the church tells to justify its place in a city that otherwise has no real use for it, the empire has never bothered to clarify, and Anubet has never bothered to ask. The wall's surface tells its long history plainly, dented and pitted so thoroughly by centuries of siege weaponry that a person could plausibly climb it on the damage alone. However, the siege weaponry lining the top makes any such attempt suicidal long before they get close.
The northern tribes throw themselves at those walls like something possessed, refusing again and again to accept the emperor's rule over them. A siege on Anubet isn't a crisis; it's a monthly occurrence, one more entry in a streak of failures stretching back as far as anyone can count. Everything about the city exists to feed that fight, its barracks housing standing armies large enough to make the constant sieges look almost routine by comparison. It doesn't have ordinary citizens so much as it has the descendants of people who came here once, generations ago, and simply never managed to become anything else.
Anubet's population sits somewhere around 250,000, split by role. Approximately 50% are workers and ordinary citizens, 40% are the standing army and guards, 5% are church personnel and administration, and another 5% are travelers passing through. That split isn't even across the city; where each group actually lives is broken down district by district. We'll begin by exploring the very heart of Anubet's industrial power, the district that quite literally makes the city's defining feature.
First, we'll delve into the Lower Foundry, a district built underground beneath the city proper, where Anubet's iron is actually born. This is the district that makes the wall what it is; ore processing, smelting, and the heavy forge-work that keeps the empire's north armed and armored all happen down here, out of sight of everyone above. It's forges and equipment and nothing else; no one lives in Lower Foundry. The people who work it go home to Upper Foundry when their shift ends.
A large portion of soldiers, and even armed church warriors, patrol its floors alongside the workers, keeping order in a district too valuable and too dangerous to leave unwatched. A conclave of fire mages works the district, their magic driving furnace-heat well past what ordinary coal fires could reach on their own. Chained at the heart of it all is a captured red dragon, its own fire bent to the same purpose: heating the forges that the mages and smiths depend on.
How the dragon was captured, who actually controls it, and what it costs to keep it compliant are all open questions the district doesn't advertise answers to. Her name is Gelunthir, and she's massive enough that the chamber built to hold her barely fits her. Moved underground long ago, into the most important sub-district of Lower Foundry, where the largest forges turn out the rarest-metal equipment reserved for soldiers of real importance. Unlike other dragons, pride isn't what defines her; what's left is subservience.
Her form still proud in outline, but her stature and her stare have gone cold, unfeeling, an animal doing what it's told rather than what it wants. She's fed several tons of meat a day, and what the city doesn't have to spare otherwise, it gives her in the condemned—criminals sentenced to death, delivered to her rather than executed some other way. Whatever ambition or will she might have had once, whoever subjugated her long ago made sure only one thing survived it: the drive to keep surviving, and nothing past that.
Now, let's talk about the practicalities of this environment: heat and air. Every forge here sits under its own hood, catching smoke before it can spread, feeding into the shared manifold that carries it up and out along the wall's outer face, so smoke is mostly handled. Heat isn't; there's no way to vent thermal energy out of an enclosed space the way gas vents on its own. Lower Foundry just absorbs it, forge after forge, with the dragon adding more on top.
The only relief is upward: large barred grates in the ceiling let the worst of the heat rise into Upper Foundry and pull cooler air down to replace it in turn. That same downward air happens to be the only thing keeping the district breathable at all, not by design, just a side effect of air actually moving instead of sitting stagnant. It's enough to survive on, but not enough to make the work anything less than brutal. This leads us to Upper Foundry.
Upper Foundry is located at ground level, roughly ten meters above Lower Foundry, and it's where most of the city actually lives. This is the district of the "failed settlers"—the ordinary residents, laborers, and tradespeople trying to build a normal life on top of a district built for war. Markets, worker housing, and everyday trade fill the streets here; there are no forges up here, all of that stays below. A large portion of soldiers and church warriors patrol these streets as well, maintaining order.
This district holds roughly half the city's entire population, and it shows in how it's built: dense streets, misshapen buildings stacked tall and crooked rather than planned, the kind of place that grew rather than was designed. Homes cluster in two rough patterns: close against the city wall itself, or in large formations set well away from the grates venting up from Lower Foundry. Most residents have picked their spot for the same reason—staying as far from the worst of the heat as the district allows.
Its population sits around 112,500, comprising about 40% of the city's total. This includes approximately 100,000 workers and citizens, plus effectively all of the city's travelers, about 5% or 12,500 people, since it's where anyone passing through without money for Sunreach ends up staying. It's a district of people born here who will die here too, generation after generation never really leaving. Most merchants passing through or working the city long-term settle here as well, at least the ones without money to spare.
The heat and air in Upper Foundry are managed differently than below. With the manifold pulling smoke out below rather than letting it drift loose, Upper Foundry's air is largely clear—smoke was never really its problem to inherit. Heat is; every grate in Lower Foundry's ceiling empties directly into this district, so Upper Foundry runs warm unevenly. Streets sitting over major grate clusters stay noticeably hotter year-round, while the rest of the district is merely uncomfortable rather than oppressive.
Let's consider a notable structure here: The Golden Gate. Facing north, a single gate of solid gold, weighing twenty tons, dominates its stretch of Upper Foundry. It was raised long ago by the church's inquisition, lifted during celebrations meant to mark the faith's own might rather than any practical need for a gate at all. It has no mechanism—no winch, no chain, nothing built to move something that heavy.
What lifted it then, and what still lifts it now on the rare occasions it moves, is raw aurumantic power alone. Most of the time it simply stays fixed in place, closed and immovable by any ordinary means; only during a crusade, called rarely and only by the church itself, does it rise again. This gate exemplifies the church's power and its unique role within Anubet.
Next, we move to Sunreach, a district set against the wall's inner face, the side turned toward the city, never the north. It's high enough to sit above the worst of Upper Foundry's smog and is Anubet's district for the city's churches and its wealthiest residents. It exists largely as an escape—clean air, distance from the noise and heat of the forges, and proximity to whatever standing the church still holds in a city that otherwise has little use for it.
None of this could exist without the wall's one exploitable quirk: driven into place and left there, iron spikes never get rejected by the self-repairing metal the way a healed-over scar would be. Sunreach is built directly onto the wall's face on massive iron spikes sunk deep into the metal, entire buildings cantilevered outward and resting on the anchors. It's a district that only holds together as long as every spike stays exactly where it was driven.
The population here is around 12,500, roughly 5% of the city's total, made up of the church, the nobility, and the city's administration. It's the smallest district by population by a wide margin, which is the point: everyone here has a reason to be up above the rest of the city, not just the means to afford it. Elevation, in Sunreach, is status made literal.
The district is built in tiers up the wall's face, and how high a building sits tracks almost exactly with how important it is. The lowest tier, about 20 meters up, is mostly warehouses, holding the food hauled up from the southern farmland along with other bulk goods. It's the least prestigious ground, but still cooler and cleaner than anywhere in Upper Foundry. This constant supply is crucial for the city's survival.
About 50 meters up, we find the noble houses and rich traders; the district's wealthy residents live here, clear of the worst wind lower tiers don't have to deal with, but not yet into the harsher air higher up. The highest tier, around 70 meters, is reserved for the council building and most of the city's churches—Anubet's actual seats of power. It's also the windiest and most exposed part of the district, though that mostly matters outside.
Sunreach answers to none of what the two districts below it deal with regarding heat and air. It isn't stacked above the forges, so no grate feeds heat into it, and the manifold's pipe is routed along the wall's face specifically to bypass it rather than pass its windows. Its reputation as the place the wealthy escape to isn't just elevation or the price of admission; it's the one district the system was built to leave alone entirely.
A notable structure here is Heaven's Spear, the council building. Sitting on the western stretch of the wall at the district's highest tier, it houses the three heads of Anubet's council and dwarfs everything else in Sunreach, being by far the largest structure in the district. Its sharp, spearing roof is the one piece of the entire city that rises past the wall itself, jutting some two meters above the full hundred-meter height of the iron below it.
Finally, we examine the Wall District. Inside the hollow of the wall itself, running the full hundred meters of its height, the Wall District houses the bulk of Anubet's standing army—garrisoned in the very structure they're sworn to defend. It is less a neighborhood than a fortress unto itself, layered floor upon floor inside the iron, facing north toward the tribes that never stop testing it. Everything military lives here: barracks, armories, everything else the standing army needs.
Not every level answers to the same purpose, though. The southern stretch of the wall, the side that's never faced a siege in four thousand years, running behind Sunreach rather than out toward the tribes, holds a smaller civilian population living and working alongside the army. Warehouse hands supporting Sunreach's storage tier, and support staff doing the unglamorous work the military itself doesn't—cleaning, counting stock, administration within the armories.
This district's population is about 125,000, 40% of the city's total, consisting of the standing army and guards, the largest concentration anywhere in Anubet. It also includes about 10%, or 25,000, civilian workers and citizens, almost all of them on the southern side supporting Sunreach and the armories. It's still overwhelmingly a military district; the south side is just where the two populations actually overlap.
Every door, window, and arrow slit in the district exists on the same terms as Sunreach's anchor-spikes: fixed into the wall on purpose, and held open only by staying in place. Sealing off a level of the district—in a breach, a mutiny, or simple decommissioning—is as final as pulling the fixtures out and letting the iron close back over them. What the wall accepts once, it only keeps accepting for as long as someone insists on it.
The manifold's pipes run along the wall's outer face as sealed shafts, carrying the city's smoke past the Wall District without ever opening into it. The garrison shares the wall's structure with that system, not its air—nothing coming through the pipe reaches the hollow interior at all. Left alone by both the heat below and the smoke passing outside, the Wall District stays livable on its own terms, its only real climate the ordinary work of holding a hundred meters of iron against the north.
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Lower Foundry's forges run on three heat sources, mainly for working iron and steel, and understanding these is key to understanding the city's industrial output. Coal is the baseline, with an open fire burning around 700 to 900 degrees Celsius, and with bellows, a well-run forge reaches roughly 1,200 to 1,500 degrees Celsius. It's most of what the district actually runs on, forming the foundation of its operations.
Mage fire is flame conjured with no fuel behind it, so it burns clean—no smoke, no soot. It scales with the mage: weaker ones sit around 1,500 to 2,000 degrees Celsius, close to bellows-fed coal, while the strongest push past 2,500 degrees Celsius, closing most of the gap to the dragon. This magical heat offers a significant advantage in metalworking precision and intensity.
Dragon fire is ignited gas rather than conjured flame, and it tops the hierarchy at around 3,000 degrees Celsius—hot enough for the hardest metalwork in the district. Coal is still what actually runs Anubet; the mage conclave and the chained red dragon push a fraction of the forges well past what coal alone could reach, but they're the exception feeding the furnaces, not the rule.
Smoke is captured at the source by hoods over every forge in Lower Foundry and carried off through a single shared manifold, run up the wall's outer face and vented a modest distance above its hundred-meter height. One shared line drafts more strongly than many small ones would, but it also means the whole system shares one point of failure: a blockage or a breach anywhere along it chokes every forge feeding it at once. Heat has no equivalent solution, only relief—it moves upward through the grates connecting Lower Foundry to Upper Foundry, rather than actually leaving the city at all.
South of the wall, well clear of the city and everything its forges put into the air, the empire's main river breaks apart into a web of smaller streams on its final run to the sea. It's along those streams that Anubet's food is actually grown; it's the one part of the city's territory the northern tribes have never reached. The wall has never fallen, so the delta beyond it has never had to be anything but farmland.
Grain fields and pasture spread across the streams' silt-rich banks, worked by generations who've never known Anubet as anything but the wall protecting their harvest. A steady line of wagons and river barges keeps the food moving into the city's storehouses. In return, Anubet sends back what its forges don't need for the wider military—surplus tools, iron fittings—though grain is what actually keeps the arrangement standing.
The supply is steady, not guaranteed; what reaches the storehouses each year depends on the harvest behind it, and the harvest isn't the same twice. A good year means full stores through winter, a bad one means shortages that don't fall evenly across the city. It's the poorer end of the population, mostly in Upper Foundry, who feel it first and worst; even in an ordinary year, going hungry on a daily basis isn't rare for them. A weak harvest only widens the gap between what they have and what the wealthier districts never notice losing.
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