It is, after all, Dungeons and Dragons. 
As much as my campaigns tend to be sandboxy travelogues that eventually transform into heroic epics, I love a good dungeon. Every campaign has at least one -- and often many -- multi-level deathtrap brimming with monsters and treasure, and on gamedays, mini-cons and the like, I often default to a Deathtrap Dungeon full of player-testing puzzles and traps and character grinding hazards. And even though I don't often use modules, I like to read solid, "old school" style location based adventures: aka, dungeons.
A good dungeon, to me, is one that offers a number of paths (as opposed to a linear room by room dungeon) that cross and re-cross, each leading to and through and equally deadly set of challenges. I like dungeons with hidden regions full of "the good stuff", as it promotes exploration. I like dungeons that have no "point" beyond, perhaps, an ultimate vault or lair.
I have experimented with dungeons with time limits and other player action forcing tools, and it always falls flat or creates an otherwise unsatisfying experience. Dungeons work best when the players explore and engage it at their own pace. And as unrealistic as it can seem, I prefer dungeons where the major inhabitants are separated enough that they don't come running from afar for every fight. Leave the otyugh in the trash pit and the black dragon in his eternal darkness labyrinth, I say. The PCs will come eventually.
Most of all, I like the dungeon specific creatures, traps and tricks. Other parts of D&D are borrowed, inspired by or stolen from all kinds of mythology, legend and fantasy. But the gelatinous cubes and electrified statues and necklaces of strangulation are pure D&D.

As much as my campaigns tend to be sandboxy travelogues that eventually transform into heroic epics, I love a good dungeon. Every campaign has at least one -- and often many -- multi-level deathtrap brimming with monsters and treasure, and on gamedays, mini-cons and the like, I often default to a Deathtrap Dungeon full of player-testing puzzles and traps and character grinding hazards. And even though I don't often use modules, I like to read solid, "old school" style location based adventures: aka, dungeons.
A good dungeon, to me, is one that offers a number of paths (as opposed to a linear room by room dungeon) that cross and re-cross, each leading to and through and equally deadly set of challenges. I like dungeons with hidden regions full of "the good stuff", as it promotes exploration. I like dungeons that have no "point" beyond, perhaps, an ultimate vault or lair.
I have experimented with dungeons with time limits and other player action forcing tools, and it always falls flat or creates an otherwise unsatisfying experience. Dungeons work best when the players explore and engage it at their own pace. And as unrealistic as it can seem, I prefer dungeons where the major inhabitants are separated enough that they don't come running from afar for every fight. Leave the otyugh in the trash pit and the black dragon in his eternal darkness labyrinth, I say. The PCs will come eventually.
Most of all, I like the dungeon specific creatures, traps and tricks. Other parts of D&D are borrowed, inspired by or stolen from all kinds of mythology, legend and fantasy. But the gelatinous cubes and electrified statues and necklaces of strangulation are pure D&D.