According to Greek mythology, which mountain was the home of the Muses and the site of the Castalian Spring?

Mount Parnassus

In antiquity, this mountain was famous for being the site of the Oracle of Delphi, where the priestess Pythia delivered prophecies. Because it was the home of the Muses—the goddesses of the arts—the name 'Parnassus' is still used today to refer to the collective world of poetry and literature.