Kilauea

Kilauea (キラウエア) is the "Land of Fire" (火の国) where Musshuru was once exiled to.

Geography
Nothing is known about the island's geography apart from the fact that the temperature there is really high since this was the only place where Mushuru could not use his devil fruit powers.

Citizens
Mushuru was once imprisoned there but no other inhabitants have appeared yet.

History
After Musshuru released a massive wave of poisonous spores that annihilated a massive portion of Drum Kingdom ten years ago. The land is most likely on fire, as he was sent here to neutralize the fire-weak spores. The Land of Fire is only mentioned during the ninth movie, and has not made an actual appearance in the series.