10 Prehistoric Clocks That Endure

10. Ishango Bone

9. Antikythera Mechanism

8. Megalithic Temples

7. Cave Paintings

6. Obelisks

5. Observatory of Goseck

4. Stonehenge

3. Candle Clocks

2. Water Clocks

1. Sundials

10 Ancient Timekeepers That Remain Relevant