D&D 3.0: Tales from Mystara
Mount Nyth is an active volcano located on White Island of the Archipelago of Ierendi. Ruins of Nithian Empire are located on this mountain but a dangerous Lillend had claimed it as her lair. Some older makai tell stories about a series of inscriptions on this ruins who tell of a magical spring somewhere located on the island. But these stories have never been proved and no makai will place a foot on the island, less stay the night in there.
Other creatures reported on the volcano are Azers but is unknown if they live on the island or come and go using a gate to the Plane of Fire.