Naxos

Naxos is an island in Greek Myths. It is where Theseus left Ariadne after she helped him go through the Labyrinth. Dinoysus, who was the protecter of the island, met Ariadne and fell in love with her. But eventually Ariadne, unable to bear her seperation from Theseus, either killed herself or ascended to heaven.

The Titan's Curse
In The Titan's Curse, Dionysus mentions it while telling Percy about Ariadne.