It is said to have derived its name from Castalia, a naiad-nymph, daughter of the river-god Achelous[2], who is said to have flung herself into the spring when pursued by the god Apollo.

[3] In older traditions, the Castalian Spring already existed by the time Apollo came to Delphi searching for Python.

In his commentary on Statius's Thebaid, Latin poet Lactantius Placidus says that to escape Apollo's amorous advances, Castalia transformed herself into a fountain at Delphi, at the base of Mount Parnassus, or at Mount Helicon.

The 20th-century German writer Hermann Hesse used Castalia as inspiration for the name of the futuristic fictional utopia in his 1943 magnum opus The Glass Bead Game.

Castalia is home to an austere order of intellectuals with a twofold mission: to run boarding schools for boys, and to nurture and play the Glass Bead Game.