What if there was like a tomb of knowledge? Hidden away and forgotten for centuries. Originaly conceived as an attempt for the different regions to work together despite their differences. Solving riddles and accomplishing certain things will give you the ability to unlock the doors.
Since the game will have multiple cultures this one location will have rooms that reflect where their from region, beliefs, or morality. Trapped in the rooms can be lore, remedies, maps to secret locations, etc.