Perhaps one of my first exports. It's supposed to be a small, dormant volcano with an irregular shape, containing a little stronghold. The mound with the banner on indicates the entrance. The exterior was made mainly with WorldEdit, and same with the lava pool inside.
NOTE: This dungeon is supposed to be inhabited by Pirates. As a result, I would NOT use the test.prop item to spawn this, as it will be a Skeleton dungeon. The download is all ready and waiting, fully set up (just plop the folder inside the zip into the DungeonConfig). It will spawn EVERYWHERE if there isn't water, and it has a 1/50 chance to generate. Once the folder is in, you can find it in your world or use the new volcano item to automatically generate it.