Related Clues:

• Primitive
• Rocky period?
• Primitive time
• Barney and Fred's day
• Early time
• Prehistoric period
• Rocky period of history?
• 'The Flintstones' setting
• Time for a mammoth feast?
• Primitive era
• Early period
• Neanderthals' heyday
• Prehistoric time
• It started about 2 1/2 million years ago
• Very primitive