This large gothic castle reminds you of the buildings found in Firedrake, and it should, the House of Iron's architects were hired to design many of the buildings there. Built into the mountainside itself, the castle is surrounded by large defensive walls which protect the legendary Astral Forge.
Unlike many of the other capital buildings you've been in before, this one seems incredibly busy; with everyone from officials to school children running the halls. At the back of the building is a blacksmith's forge, where students from across the lands come to learn from the founding families.