Related Clues:

• As old as the hills
• With 31-Across, literary character 'whose beard with age is hoar'
• Very old
• Like Stonehenge
• Long-ago
• Old as the hills
• Long gone
• Socrates or Pythagoras, e.g.
• __ history
• Like the Parthenon
• Primeval
• With 21 Down, old salt
• Like dinosaurs
• Age-old
• Aged and timeworn