Spring of Pieris

In Greek mythology, the Pierian Spring of Macedonia was sacred to the Muses. As the metaphorical source of knowledge of art and science, it was popularized by a couplet in Alexander Pope's poem "An Essay on Criticism" (1711): "A little learning is a dang'rous thing; / Drink deep, or taste not the Pierian spring."

The Pierian spring is sometimes confused with the Castalian Spring.

The sacred spring was said to be near ancient Leivithra in Pieria, a region of ancient Macedonia, also the location of Mount Olympus, and believed to be the home and the seat of worship of Orpheus. The Muses "were said to have frolicked about the Pierian springs soon after their birth". The spring is believed to be a fountain of knowledge that inspires whoever drinks from it.

Ovid provides the tale of the origin of the Pierian Spring in Metamorphoses V. The Muses – in particular Urania – tell Minerva how Pegasus struck the earth with his hoof, from whence the spring arose:

"And where a path, high over the deep sea, leads the near way, she winged the air for Thebes, and Helicon haunt of the Virgin Nine. High on that mount she stayed her flight, and with these words bespoke those well-taught sisters; “Fame has given to me the knowledge of a new-made fountain – gift of Pegasus, that fleet steed, from the blood of dread Medusa sprung – it opened when his hard hoof struck the ground.—It is the cause that brought me. – For my longing to have seen this fount, miraculous and wonderful, grows not the less in that myself did see the swift steed, nascent from maternal blood." To which Urania thus; "Whatever the cause that brings thee to our habitation, thou, O goddess, art to us the greatest joy. And now, to answer thee, reports are true; this fountain is the work of Pegasus," And having said these words, she gladly thence conducted Pallas to the sacred streams. And Pallas, after she had long admired that fountain, flowing where the hoof had struck, turned round to view the groves of ancient trees; the grottoes and the grass bespangled, rich with flowers unnumbered – all so beautiful she deemed the charm of that locality a fair surrounding for the studious days of those Mnemonian Maids."

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Wikipedia