I have a question: does anybody have a notion as to why Arneson, Gygax, and the rest chose to set their game in underground labyrinths?
I'm primarily interested in actual, confirmed/widely-suspected ideas as to why this is (design notes, for example), but I'm moderately interested in your speculations, as well.

I will offer a partial speculation of my own: a confined setting, like that of a fortress or cave complex, is probably the best combo of exciting and clearly delineated/confined. But I don't know why the design even came up in the first place, such that they really wanted to focus on a closed, confined space. Yes, we can see the practical applications for it now, but why and how were they hatched upon in the first place?

Ideas like traps, mapping, etc., all rely on a fairly stable, established space for the adventure. But encounters and treasures require somewhat less spatial precision. Hm.

The old story I've heard comes from the wargame Chainmail -- there was a scenario involving a siege on a large castle.  The invading army tunneled underground into the castle's dungeons, came up, and raided the place.  Playtesters loved the dungeon scenario and found exceptional fun in an unexpected place; eventually the concept was expanded and turned into Dungeons & Dragons.

An old gaming group of mine came to the conclusion that back in the early days of rpgs the idea of enclosed places was cool, because people lacked them, and now we found that more games are moving towards the outdoors, because we now have moved from spending time outside to places that are more like the setting of the older rpgs cool enclosed places. It seems that we move away from what we commonly deal with in everyday life.

Just an idea.

The thread stops here unless you can ground it in actual play. Consider your experiences which raise the question of of the thread title. I'll move it to the Actual Play forum in that event. Otherwise, the thread is closed.

Best, Ron

Some Actual Play:

In playing some 4e recently I experienced the effectiveness of dungeons as fictional settings that facilitate certain types of play.

The finite dungeon is a finite space.  My early D&D play (circa 1980) gave me experiences that are confirmed by academic game theory: there are a finite number of optimal strategies for making decisions in a finite space.  Even if you have "n" and not 2 players, if all entities have rule-governed courses of actions, you can prune suboptimal decision tress and commit to a range of stragegies with at least of some sense of the risks you are taking.  When the GM was pulling "surprises" or adding "clever" twists -- bringing in agents and effects from outside of that finite space -- I always got annoyed.  The surprise "villains get away 'cause I need them for the next adventure" ticked me off too.  I was using my finite resources in a number of game-appropriate ways and now you totally blow apart the constraints in which I made my decisions?  Screw that!  I used to think that I was interested in stories that D&D couldn't tell but what I was really frustrated with was people who were messing with the parameters that made a game gamey.

AND I was frustrated that D&D couldn't get certain fictions going.

But recent 4e really lays out the game-y ness of the game and I have found it rewarding.

My requirement for actual play in the post needs to be met by Abkajud. After a little more thought, I now recommend that this thread would do very nicely in Playtesting with a bit of context from current play of Mask of the Emperor.

Best, Ron