Location: Pouderin Keep

I decided to do another picture today. This time, though, the image is from Reddit user Pouderpuff. Since he didn't name the picture, I dubbed it "Pouderin Keep" in honor of him. Also, I decided that I would only post on weekdays. This is already of low quality as it is, and I'd like to spend at least a little more time on each post than I have been.

Description: The castle sits atop a small island in the ocean. The sun gleams off the white stone in a majestic fashion, nearly blinding you as you approach. The air is salty from the sea, and the wind blows perpetually. The nearby area is nothing but cliffs and jagged stone. The keep itself is made from a white stone, and shows the wear from the sea over the course of the years. The keep tunnels down into the rock it is located on, and it seems to you that it must even go underwater. You have a slight sense of claustrophobia inside the cramped halls.

Associated Knowledges:
History:

• This keep was built many centuries ago, and has always been owned by the same dwarves.
• The Bilder clan of dwarves crafted this keep, and it has always been owned by one of their patriarchs.
• The dwarves use this fortress as a secure point to fall back in case of war. This has happened many times during their history, and the keep is virtually unassailable.

Geography:

• The location of the keep makes it very secluded.
• The difficult terrain surrounding the keep prevents easy travel, even to the dwarves that live nearby and inside the keep.
• The keep itself is made of a stone that is not found in this region.

Dungeoneering:

• The keep appears to be built solidly. You can't identify any faults in the inside structure.
• The keep is made out of a porous stone that would resist any sort of siege weapons.
• You can tell that the keep extends far beneath the waterline.

DM Info:
  Pouderin Keep is an ancient dwarven fortress. The Bilder clan of dwarves regards it as the one location that they will definitively keep - pun fully intended - forever. In times of crisis, they have retreated to Pouderin Keep to hold out against invading armies. Every time, they have repelled the attackers without issue. It is built in such an unassailable location, and is made of a stone that is nearly impossible to breach. The material is similar to coquina, but is an actual stone. Siege weapons basically have little to no effect on the keep's walls. What is interesting is that this stone is found nowhere near the keep. In fact, it's not located anywhere in territory that the Bilder clan has every controlled. The Bilder dwarves have actually found a way to fabricate the stone, and do so in secret. It is very difficult to do so, which is why they only built the one keep. Most of the Bilder dwarves are obsessed with finding ways of making the process easier, to give them an advantage against invaders.
  The keep is inhabited mostly by dwarves and a small number of gnomes. This keep is to the south of the Bilder territory, and only has a few defenders. A minor patriarch is given control of the keep, almost as a token measure. However, in times of invasion the keep becomes a major strategic lynchpin to the dwarves, and that patriarch's status is elevated. This is, I feel, the biggest plot point that the keep can offer. The patriarch plans to start a war with another nearby clan, so that the Bilders will be forced to rely on his keep. This will make him a valuable member of the clan, and allow him to advance out of the Pouderin Keep. 
  Inside, the keep resembles most dwarven homes. Narrow tunnels, deep shafts, and underground mining. The keep extends far below the waterline, and has hit the earth below the relatively shallow sea. They are free to extend their operations as deep as they please without threatening the integrity of the keep. However, due to the small number of dwarves and gnomes that live there permanently, the operation is slow and inefficient. Mostly they spend their time readying the battlements in case of invasion. The tunnels, however, do still have a number of underground creatures living in them. The dwarves are oftentimes overwhelmed by the sheer number of monsters that inhabit their home, and are unable to do anything but slowly weed them out. Sometimes they will hire mercenaries to do it for them, but this is seen as highly insulting to the patriarch's honor, and is only done in times of great need.
  There is little trade to Pouderin Keep. Shipments of food and supplies come every now and then from the Bilder clan, but little else makes it's way there. No merchant is willing to risk the dangerous terrain for the little business they might drum up in the keep. Especially since dwarves are notoriously territorial, and may take offense to such actions. Luxury goods are very rare in the keep because of this. The dwarves that live there keep their lives fairly minimalistic. They keep to their tunnels, mining away slowly, and readying for a war that may never come. They keep their tradition highly insulated, and rarely see newcomers to the keep. 

Adventure Hooks:

• The tunnels are overwhelmed by monsters. The dwarven patriarch puts out a call for adventurers to help them reclaim their home.
• The patriarch is weary from boredom. He is scheming to start a war to elevate his position, but needs the PCs to help him.
• A merchant is willing to make the trip, provided that he has an escort.