The Citadel is an archive of information for George R.R. Martin's A Song of Ice and Fire.
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The Freehold of Valyria was apparently destroyed in a cataclysm. This disaster was dramatic enough that it is represented in art (I: 29). Given the "smoking ruins" (I: 374), the Smoking Sea (III: 98), and the shattered appearance of the peninsula that was Valyria, it is likely that the cataclysm was volcanic in nature. This parallels standard interpretations of the fall of Atlantis, which is the likely inspiration for the Doom.
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