The Gygaxian Gyre is a deep and vast place, and the Perrenian Necrohol is one of the zones of the dungeon that almost all explorers lucky enough to survive the Gyre proper are introduced to

Often colloquially named Terras'stone, it is the greatest city in the DungeonVerse

A classified biotech research lab located in the Shadowlands. A place where the Tankado Clan performs secret and sometimes dangerous experiments with various lifeforms and machines outside of the reach of the Rokugani Empire. For use in the Legend of the Five Rings RPG.

An underground bunker complex built inside a cave system. The entrance to this hidden base is close to a small village deep in the mountains. Currently it is the headquarters of the rebel group known as the Nakatomi Enclave.

Half found, half built, abandoned more than once, reclaimed more than once, and now occupied by the Neo-Soviet branch of the Glassenheim Foundation

Also known as the Dungeon of Deception, Belgar Nakaleth appears like a lost subterranean city

Pay Here, Stay Here, Play Here

Few know of this place, and far fewer know of its location. This is a good thing, for nothing wholesome comes from here.

When you live at the bottom, the only thing you have is to look up. If you're lucky you can see the lights of the great towers and the stars. If you're like most people, you just look at concrete. But the stars and lights are still up there.

How long they carried him through those back tunnels, illuminated only by the flickering of torchlight, he had no idea. Then light seemed to explode when they reached the massive chamber. All around, unbelievably large red crystals captured the light of the flames and seemed to multiply it.

Troth Glenbeard was a dwarf with a mission. And that was destruction.

From there, things happened. And the Irondeeps got a Subterranean-Transport-System-That-Moves-Things-Around-Faster-Than-Equine-Means (aka, in modern-speak, a subway).

One of the largest and most famous cryodetention centers operated by Creative Incarcerations Corp

One of the largest and most important military bases of the Atlantic Federation

A dangerous, alien plane where glowing frog-slimes slither and slurp, metal-skinned bird people rebuff diplomacy, and only the endless subterranean tunnels are safe (just mind the gravity-bending moles). Visitors will have to skulk around in the dark to avoid the curse carried by the sunlight. Because (have I mentioned?) the sun is the source of a powerful curse--one that covers the whole planet.

A subterranean prison complex, meant to incarcerate those who need to be removed from society.

The blighted and forgotten hall of a once mighty demon lord

What lies under the turf deep in the earth of that grassy mound? The PCs would very much like to know...

Great, mysterious chambers hidden deep in the earth beneath that enigmatic city of Stoneholt!

The product of centuries of slow, careful, painstaking work, a testament to the Old Ways and the power of Thaumaturgy, the Cathedral of Light is known of across the whole of Kuramen.

Inspired some years ago for a Kult/CoC Halloween game