So, everyone knows a good dungeon map when they see one. A layout that provokes interesting navigational decisions and has memorable locations. But what are the principles underlying the creation of these things that can be used to make such a dungeon? What are the rules to follow?

Most of the time when I make a dungeon map, it feels like just picking hallways and rooms at random, and there isn't a feeling of inspiration behind it. There is no guiding vision or eureka moment that makes me feel like I'm onto something. Even things like "jacquaying", while making sense in the abstract, doesn't quite land when actually making one.

How does everyone else do it? Is there a list of procedures to follow or a series of principles that go behind designing good dungeon maps? Or is it all just 100% from the gut, an intuitive effort?

I always design my dungeons as real world locations, starting with purpose. I tend to find that most of the other components of dungeon design follow naturally when you have a good idea what a place's history is.

You want a classic dungeon? Start with a broken down and abandoned castle which once defended a (-insert metal here-) mine, but has been abandoned for a generation or so. Challenges can come in the form of broken parts of the castle or mine. The entry bridge may have collapsed, the door is rotten and not functional, the mine's main entrance has fallen in and is only accessible through a second entrance. Encounters can be populated with things which have moved in. The castle has now been taken over by a variety of wild animals seeking shelter, and the mine may quarter some bandits using this as a hideout or some other big nasty.

Now, you have real world considerations to help you build the location. Was it trying to defend a high ground location? How did it get water? Where's the latrine? What items can I scatter around to indicate the past and present of this location?

Let's go in another direction. Let's say the location is a stereotypical wizard's tower a la Orthanc. What specific tasks was the wizard doing here? What staff and security is present? If the wizard is doing human chimerism experiments, chances are that's in a pretty secure part of the tower, and is guarded with less crazy experiments like constructs. There are probably a good number of traps intended to capture whoever is breaking in. The wizard may have put security clearances in place to keep his own minions from finding out too much.

Those are all interesting things to design and naturally lead to a unique location.

I don't know about the "right way" to do it.  I can tell you how I go about it. 

I'm attempting to balance several things at once, including logic, principles, gut, instinct, aesthetics, and a few more.  I don't have a particular mix, but the ones that have worked the best were such combinations.  My general guidelines would include, in no particular order:

- The multiple paths should include both horizontal and vertical elements, at a minimum.  If you can throw in something more exotic, all the better (slides, 1-way doors, teleporters, etc.), though those can be done too much.

- Multiple paths should, whenever possible, also have multiple entrances/exits.

- The place should have some verisimilitude with the setting and the tone of the game (of course), should invoke something "natural" for that environment, but should also have fantastical elements, or at least a few twists.  (I want an abandoned keep to be "ruined" in semi-realistic ways, have some traps that are really hazards from the decay, but also have enough room to move about, which isn't exactly fitting with the source material.) 

- Wandering monsters should mostly come from the denizens or things that can lurk around the edges of the main inhabitants, but throw in a few wild cards.

- The factions in place should be stable enough to explain how they got to that state and don't immediately collapse into something else, but unstable enough that clever players can push in the right places to get an advantage.

- It's better to have several traps in a location that makes sense, that isn't traveled much by the inhabitants, than to have random traps sprinkled all over the place.  Though every now and then, someone has set something new.  New traps in the no-man's land between factions makes a lot of sense, while old traps in the abandoned areas likewise.  Players that learn about the area can somewhat predict those.  Even so, it's also a good idea to have about double the number of traps you want, but make some of them repeats that are either already sprung or give plenty of warning--blood stains, scorched surfaces, etc.  Heck, I once got a ton of mileage out of nothing but old, sprung traps.  It made the party nervous, to the advantage of the creatures that were the real threat.

- Unless it's just a one-shot, the dungeon should have an effect on the surrounding area and vice versa.  There should be things happening in the nearby towns, villages, and the wilderness between them, because the dungeon is there.  There should be someone in the dungeon that cares somehow about those happenings.  You don't have to be original here, or even very subtle.  A little connection goes a long way.

- Rarely should the dungeon be all one environment--clean corridors with the same stone work, air quality, etc.  Toss in something, even if it only has a minor effect.  Flooded areas are great, but so are ones that simply damp or moldy.  Drafts that are considered carefully give clues, and a reason to vary temperature. One rough cavern in a worked complex jumps out. 

- If you aren't playing a game that tossed out lighting entirely (whether making magic light easy to get or giving most everyone the ability to see in the dark), you've got a huge tool in your arsenal to set mood, tactical situations, and player doubt.  Even better when a lot of the monsters can't see in the dark either, and thus some places in the complex are lit by them.

That's hardly everything, but it's a good summary of some of the key things I try to keep in mind.

Honestly, I don't like 99% of dungeons I see.  Knowing a bit about structure and materials most of them would be unsustainable.  Also, most of them are impractical except as a maze of death and that bothers me.  I much prefer something that looks like there was a use for the space.

I use maps of RL castles, underground cities (there are a few in the Middle East and Asia), sewers, and subways as dungeons.  It may not make for better game play but it helps me as a GM not have to fight the internal itch the whole game session.  My favorite I ever ran was a series of slot canyons with some caverns. 

Honestly, idk if my dungeon philosophy would work for anyone else but it seems to work for me and my players seem to enjoy it.

Quote from: mAcular Chaotic on August 20, 2023, 05:22:39 PM
So, everyone knows a good dungeon map when they see one. A layout that provokes interesting navigational decisions and has memorable locations. But what are the principles underlying the creation of these things that can be used to make such a dungeon? What are the rules to follow?

Most of the time when I make a dungeon map, it feels like just picking hallways and rooms at random, and there isn't a feeling of inspiration behind it. There is no guiding vision or eureka moment that makes me feel like I'm onto something. Even things like "jacquaying", while making sense in the abstract, doesn't quite land when actually making one.

How does everyone else do it? Is there a list of procedures to follow or a series of principles that go behind designing good dungeon maps? Or is it all just 100% from the gut, an intuitive effort?

https://donjon.bin.sh/fantasy/dungeon/

While I've started from scratch before, I find it saves me effort to take something from the internet, and tweak it for my purposes.

Jaquaying is good dungeon advice. There's a game aspect to dungeon design or any adventure, really.
Does it make sense? It doesn't have to make sense to make sense, but it should make sense on some level. I'm a fan of funhouse dungeons, but even a funhouse dungeon should have some explanation for why it's the way it is. Mad wizard, corrupting presense, mythic underworld, etc.
Super Metroid is a good example of how to design a space for exploration challenges. Encounter the "lock" before finding the "key".  Hint at things deeper into the dungeon.
And keep in mind the dungeon should serve the adventure. I've had simple cave lairs that were only 5 or so locations with a few corridors, because it's just a cave... the encounters within were the point.

Quote from: mAcular Chaotic on August 20, 2023, 05:22:39 PM
So, everyone knows a good dungeon map when they see one. A layout that provokes interesting navigational decisions and has memorable locations. But what are the principles underlying the creation of these things that can be used to make such a dungeon? What are the rules to follow?

There are none.  I design the dungeon for what it was originally build/dug for.  If an old abandoned Dwarven mine then design it like that.

Okay, I tend to like realistic, rational dungeons.  So if there's a spring or counterweighted trap, there's a skeleton or a golem or something somewhere that's tasked with reloading it.  There tend to be storage rooms, barracks, bed rooms, halls, training areas, a water supply, and a midden.  The undead don't need such things of course.  Generally the better and tougher stuff is farther in or deeper down.  Dragons and large monsters must have viable exit points, for flying monsters there will either be a large shaft or a high rookery.  Larger chambers will have pillars often carved as statues but structurally significant none the less.  If you want a really nasty trap, animated structural statues.

When drawing the map I tend to start at the entrance and work from there putting defenses and vending machines nearby.

Okay, so the vending machines in the current dungeon I'm running are animated constructs.  One has healing potions and the other has rations and useful items.  Naturally, when the PCs try to break into them a booming voice rumbles "More people are killed by vending machines than dragons, every year."  Giant mallets pop out of the sides and begin swinging as the machines charge forward to crush the thieves between them.

The problem with making it "realistic" is it can be an un-fun or boring location to actually play in.

A good dungeon has to be fun as a gaming location in addition to it having any other concerns.

When I look at a room, deciding if there should be 2 exits, 3 exits, 4 exits, a ramp, hallways, anything, I have no idea what should come out of it.

It all feels so arbitrary. But there's definitely good and bad dungeons, so there has to be something to it, that makes these decisions good or bad ones.

Quote from: mAcular Chaotic on August 20, 2023, 05:22:39 PM
So, everyone knows a good dungeon map when they see one. A layout that provokes interesting navigational decisions and has memorable locations. But what are the principles underlying the creation of these things that can be used to make such a dungeon? What are the rules to follow?

Most of the time when I make a dungeon map, it feels like just picking hallways and rooms at random, and there isn't a feeling of inspiration behind it. There is no guiding vision or eureka moment that makes me feel like I'm onto something. Even things like "jacquaying", while making sense in the abstract, doesn't quite land when actually making one.

How does everyone else do it? Is there a list of procedures to follow or a series of principles that go behind designing good dungeon maps? Or is it all just 100% from the gut, an intuitive effort?

AD&D 1e DMG, Appendix A: Random Dungeon Design. All you need 

As far as traps and monsters I use my Rule of 30: every 30 feet the party should run into a trap or monster.

Quote from: mAcular Chaotic on August 20, 2023, 07:18:30 PM
The problem with making it "realistic" is it can be an un-fun or boring location to actually play in.

A good dungeon has to be fun as a gaming location in addition to it having any other concerns.

When I look at a room, deciding if there should be 2 exits, 3 exits, 4 exits, a ramp, hallways, anything, I have no idea what should come out of it.

It all feels so arbitrary. But there's definitely good and bad dungeons, so there has to be something to it, that makes these decisions good or bad ones.

I think your problem is that you are trying to do both tasks--be fun and realistic--at the same time. That's usually not how I do it. I start with broad strokes of realism, then ask, "how do I make that fun?" and then when I run out of ideas I go back to thinking about realistic needs, and then switch back to thinking about how to make it fun.

A realistic dungeon, of course, is a set of prison cells.

Quote from: Ratman_tf on August 20, 2023, 11:21:51 PM
A realistic dungeon, of course, is a set of prison cells.

No a realistic dungeon is an inner tower in a castle.

I don't know that I have an objectively good set of principles for dungeon design, but I'll share what works for me.

First, dungeon design doesn't happen in a vacume.  I design the adventure first, then create the dungeon to fit the adventure.

I treat the adventure design like writing a story.  Yeah I know, games are not stories, blah blah blah ad nauseum, but storywriting techniques are very useful when designing an adventure as long you keep in mind that the players will make their own decisions, so a great deal of flexibility has to be incorporated.  At the start of the story, the PCs get a mission or a goal, at the end comes my expected ending, and in between are a set of significant events or encounters, arranged in a sequence of rising or falling tension with interludes or even comedy relief, the last of which is usually the climax with a BBEG.  I'll also think up a list of less important encounters that can be thrown in anywhere.  And I like to put in some foreshadowing of future encounters.

Next comes a bubbles and arrows plan, showing which encounters lead to which others.  This is where the flexibility comes in.  The players can decide what path they will take, but every path to the end should follow the plan for rising and falling tension etc. and include enough steps to fill out the expected gaming time.

Then I finally get to the dungeon.  From the adventure design I already know the type of location, natural caverns, dwarven mines, ruined city, monster-dug tunnels, whatever.  Most locations are purpose built, so this informs the design.  If it's a ruined castle, it will have a throne room, bathrooms, kitchens, bedrooms, barracks, etc.  I'll sketch out the layout or borrow something from a public source.

Then I place the encounters at appropriate spots on the map.  If I want event A first, it might happen on approach to the dungeon or in the main entryway.  If I want encounters B, C, and D to follow A there will be obvious paths from A to each of these.  The map gets modified to conform.  Hallways might be added or walls collapsed.  A room where I want a particular encounter might gain an extra 20 feet of height with balconies.  Then the minor encounters get scattered in places where they might be run into between major encounters.  I'll also consider interaction between encounter areas,  If there's an orc encampment near a hellhound den, why haven't they killed each other?  Maybe one or the other is new, or the orcs feed the hellhounds, or they've built barriers.  It may be that every room will be an encounter or it could be only one in 10.

Last I consider reactivity.  If the orcs in a room are attacked, one may run for help to the main campsite, yell, or sound the alarm.  If the PCs retreat from the encounter, the orcs may leave, reinforce, erect barriers, or construct traps.

I'll usually have a theme for the dungeon:  it might be mostly humanoids, or slimes, or traps, or undead.  Everything will have a logical explanation for being there.  There won't be any monsters locked in a room with nothing to eat.

For the encounters themselves, I try to get a variety.  Usually mostly combats, but also traps, puzzles, stealth, and terrain traversal.  I like areas where smart tactics can create a significant advantage.

It's really important to have alternative methods to get through the adventure, because single point failures suck.  If the only way of getting the McGuffin is to spot the secret door it's hidden behind, then a single roll can cause the adventure to fail even if the players did well at everything else.  Don't do that.

The last thing is to let the players loose in your playground and be flexible when (not if) they don't follow any of your expected paths. 

It has to have a function and not be there just to be looted by PCs. Or more accurately it should feel that way even though it will be razed to the ground.

The layout shouldn't be arbitrary or just silly (IE have a logical layout).

It should be smaller much like the building of the ancient world.

It should have a reason to exist - this kind of crosses over with the first point.

And can't be populated by random monsters that could not ever coexist.
YMMV.