Parnassus is one of the largest mountainous regions of Mainland Greece and one of the highest Greek mountains. It spreads  over three prefectures, namely of Boeotia, of Phthiotis and of Phocis, where its largest part lies. Its altitude is 2,547 meters and its highest peak is Liakouras. To the Northeast it is connected to Mt. Giona and to the south to Mt. Kirphe. It was named after the homonymous hero of the Greek mythology, son of Cleopompus (or Poseidon) and Cleodora, who had built on the mountain a city which was destroyed during the Deluge of Deucalion. Etymological analysis, however, shows a pre-Hellenic origin of the name and alludes to the Pelasgians. 

The mountain is delimited to the east by the valley of the Boeotian Kephissus and to the West by the valley of Amphissa. The geological particularity of Parnassus lies in its rich deposits of bauxite, which have been systematically mined already since the end of the 1930s. 

The significant biodiversity, both in flora and in fauna, led the authorities to establish the National Park of Parnassus already in 1938. The Park comprises a landscape of 36,000 acres spreading on the mountainous region between Delphi, Arachova and Agoriani. Among the endemic flora species under protection are the Cephallenian fir tree and the Parnassian paeonia (paeonia parnassica). In the Park sojourn prey birds and wolves, boars, badgers and weasels.  

Close to Arachova there is a ski resort functioning since 1976, with two slides, one in Fterolakka and one in Kelaria. 

Myths and legends of Parnassus
Parnassus was considered a sacred mountain in antiquity, possibly second in sanctity to Olympus. According to mythology, Deucalion and Pyrrha landed with their ark on its peak during the deluge. Another relevant myth relates that the inhabitants of the city built by the hero Parnassus were the only ones saved from the deluge, as they followed the hurling of the wolves and climbed to a height above the level of the deluge waters. On that spot they founded a city which they named Lykoreia. The modern name of the highest peak of the mountain, Liakoura, probably resonates the ancient city's name.  
The mountain was related to Apollo at a very early date. It was believed that Apollo met Orpheus here and gave him the golden lyre and the charisma of pacifying the wild animals with his voice and song. Here, again, Apollo killed the Python, the horrible serpent which guarded the sanctuary of the chthonic deities, and acquired the gift of divination, which he transferred to his priestess, the Pythia. 
The Corycian cave, the cult cave dedicated to Pan and the Muses, is situated at a height of 1360 meters on the slopes of Parnassus, at a site of impressive beauty. Excavations brought to light remains that attest to the usage of the cave from the Neolithic down to the Roman period.