Is it possible that ancient cultures were interconnected thousands of years ago? According to thousands of underground tunnels that stretch from North Scotland towards the Mediterranean the answer is a big yes. While the reason behind these sophisticated tunnels remains a mystery, many experts believe that this huge 12,000 year old network was built as a protection against predators and other dangers 12,000 years ago. Some experts believe that these mysterious tunnels were used as modern-day highways, allowing the transition of people and connecting them to distant places across Europe.