Structures Still Standing in the Ruined Underworld City

Stand by for enlightenment!

d12
1.  Gymnasium of the Ancients: single colossal room like torture chamber writ large, engines of anguish in row after row, scattered free weights, less recognizable contraptions, all seemingly designed to invoke misery, swampy due to leaky roof, self-contained ecosystem, two factions of rat-sized mutant bacteria devour one another, locked in evolutionary race for supremacy
2. Posh dwelling, protected from apocalypse by powerful enchantment, three stories, luxuriously appointed, totally refinished dungeon basement, occupied by cranky matriarch-lich, officious, hidebound, family fortune dwindles but still deposits quarterly tax payments in special receptacle on outskirts of property overflowing with gold
3. Commercial bakery w/surprising level of automation, pressurized tanks still hold liquid creme filling, leaks slightly from valves, still edible, powerful hallucinogen, troop of lesser subterranean apes housed within developing religion around ritual imbibing of creme filling
4. Manufacturing plant beneath concrete bunker contains all necessary parts to construct working hovertank should requisite extremely costly research be completed/smoke-breathing sub-dragon be evicted
5. Control sphere atop impervious ceramic tower powered for 1d6 x 10 minutes if emergency generator at base can be activated, if so, spinning knobs, pressing buttons, flicking switches in correct sequence triggers nuclear strike on other side of continent from concealed silos
6. Warehouse building loaded with iron tools of every stripe, packaged construction materials, troop of hardhat/safety glasses-wearing, wrench-wielding lesser subterranean apes develope culture based around these mysterious objects & their presumed spiritual significance
7. Tiny single story dwelling & once impeccable garden, protected from catastrophe by some godling's petty whim, inside one short, bent human skeleton, 1000 cat skeletons, after years untold, still smells  like cat piss, no treasure
8.  Heavily shielded apothecary's steel door yet to be breached, security cabinets hold pills, powders, liquids of every conceivable medicinal purpose, 85% anti-anxiety pills
9. Partially buried by rubble from adjacent tower, grand marketplace remarkably well preserved, stalls now occupied by vendors of evil, high-level sorcerers teleport in for shopping sprees
10. Ink bottle & stylus-strewn office, heap of ledgers set ablaze just prior to catastrophe, multiple safes, coffers, lock-boxes, chests, all emptied of loot by fleeing accountants, used as way-station by travelers (2 in 6 chance of often jumpy/paranoid itinerants), sealed bins hold rations, effervescent water bubbles up from exposed pipe, mildly radioactive
11. Swanky family dome: surface levels emptied of loot long ago, grim scene of lethal post-catastrophe family-on-family violence discernible from archaeological evidence, fully stocked wine cellar still holds collection of black, viscous, utterly lethal poisons, several deceased subterranean apes clutching half-empty bottles
12. Former ballroom, perpetually thumping sound system intact, powered by depleted chaos batteries, elite subterranean ape shamans make pilgrimages to receive divine revelations from looping selection of remixes, hypnotic light show