Why didn't I post a thread about this? My D&D group also decided to look at a fortress once, here are the relevant bits.
The group was trying to sneak away from a battlefield where their king's army had been hopelessly overwhelmed. Under a heavy fog of magic origins they come across an old dwarven road and decide to follow it to find a hiding place before the fog lifts.
I had the entire fortress exported, the colors inverted and printed out in greyscale. For background, the fortress had been overrun and plundered by goblins many years ago, but the most treasured artifact was still hidden at the very bottom, at the shore of an artificial underground lake. For enemies, the castle was largely empty beside some nasty critters, a large cave spider in the catacombs, a goblin adventure party looking for treasure, drakes nesting at the upmost spire and the last, mad survivor of a dwarven reclaiming party, hiding away in the main lever room, pulling random levers following his whims.
One out of the three players had played dwarven fortress before, the other two where quite confused since the dungeon didn't follow common RPG logic. Turns out this was difficult for me as dungeon master, too, since the player tended to spend way to much time pondering oddities that any Dwarf Fortress player would be familiar with:
* The road they followed was partially engraved. They found images of dwarves talking to elves, cheese, dwarves killing elves, dwarves killing goblins and of a legendary table. The players tried to make sense of it but gave quickly up since all the pictures didn't add up to a story. But they rightfully deduced that there were crazy dwarves ahead.
*The rogue was scouting ahead and found a small wooden hut in the woods, Looking like this:
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#^^^^^#
#C^^^^|
#^^^^^#
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"C" is a simply stone coffer, the traps are cage traps. I originally build this just for the heck of it as a painfully obvious idiot trap, but I actually managed to trap a tiger and two goblins with this. After having a narrowly dodged cage dropped on him, the rogue looked under the roof of the hut and was menaced by the trap mechanisms, but managed to disable them and retrieve the valuable treasure in the coffer: A single goblin bone bolt. I actually intended the worthless bolt to show the players that they were baited in the trap, but for some reason they had the idea that the bolt was an important plot item and held on to it dearly. Because, hey, there must be a reason why it was protected by so many traps, right?
* After watching the walls for a while, although they didn't like all the many arrow slits they crossed the moat and went through the open door to enter the fortresses' outside courtyard. They were lucky to do that instead of entering by the small opening in the mountainside since they managed to avoid the trap corridor this way.
* The entire courtyard and half the fortress was cluttered with fine silk stockings, narrow loincloths and other clothing items. The group was quite confounded by this and came up with various theories like dwarves being teleported out of their clothes, dwarves being eaten out of their clothes, spontaneous combustion and so on. But in the end the players arrived at the right conclusion: Dwarves are slobs.
* The group entered the fortress by the great drawing bridge, walked around a corner and suddenly in the same moment it gets a bit darker, a loud BANG reverberating through the tunnels is heard and a gust of wind felt. Was it an explosion inside the mountain? Somebody casting dark magic over them? A teleportation effect? A ghost passing by them? They never figured out that the mad dwarf in the tower just happened to pull the drawbridge's lever and that they were effectively trapped.
* Of course the fortress includes a grand statue garden in a lavishly engraved hall. In D&D statues usually can be either things: A trap that does something like shooting fire from its eyes, or a golem that just hasn't moved.. YET. So coming across a hall with 30+ statues made the group advance very, very, cautiously. Only after some hiding behind shields, poking, pushing, and finally breaking one the players believed the statues to be harmless.
But such a hall has to have some meaning, right? And there's a well in the northern corner! Who would need a common well in a fine hall such as this?
* The rogue was winched down the well and discovered that there was a passage to a stairway a bit below, connecting to three other well shafts. In the context of Dwarf Fortress, the stairwell was only an auxiliary construction left over from digging the shafts that was walled off from the rest of the fort to keep invaders from using it. But for the players it was a secret passage, possibly leading to hidden treasure! Luckily they decided to climb upstairs and leave at a well near the treasure chambers, otherwise they would have been sorely disappointed.
* They left the fortress at an exit leading to a high plateau devoid of any trees to find a narrow line of piles of boulders, right next to several windmills. What could this mean, was it a fortification, was something buried below it? Of course, from their vantage point the adventurers could not see the platform high up the tower where the catapults are stationed. But by this time the players had already learned that a dwarf fortress is a place where not everything makes sense, shrugged, and simply went on with their adventure.
The group never managed to find the treasure since a change of schedule and players lead to starting an entirely new campaign. But I am still keeping the floor plans, they may come back to reclaim what is theirs.