Possible Clues:

• To pile Pelion upon - is to make even greater
• Mount near Mt. Olympus
• Greek mountain's huge appeal
• Legendary mountain in Ross and Cromarty
• Olympus' neighbor
• Peak SE of Olympus
• Pelion sat on it
• So as to make no bones about it? Just the opposite!
• Peak in 'The Odyssey'
• Mountain in east Thessaly in northeast Greece