Nisyros is one of the youngest volcanic islands in the Aegean Sea, located between Kos and Tilos. According to ancient Greek mythology, it was formed during the battle of the gods with the giants: Poseidon broke off a piece of the island of Kos and threw it at the giant Polybotes, creating Nisyros.
https://travelua.com.ua/en/world/greece/nisyros-island-a-journey-to-an-active-volcano.html

