### Shocking Discoveries in Tunnels
Tunnels always evoke a creepy feeling – they are long, dark, and deep underground, creating an indescribable atmosphere of mystery. Therefore, it is no wonder that many terrifying discoveries have been recorded here. Here are some of the most terrifying discoveries ever found in tunnels around the world.
1. Ice Age Caves
Many people think that man-made tunnels are simply passages dug by humans or animals, with nothing special but rocks. However, the Earth has a history of millions of years, and when we dig deep enough, we can find ancient traces.
In 2017, a cave under the city of Montreal, Canada, was discovered when explorers accidentally opened a new passage in the limestone layer. This cave is about 15,000 years old, existing since the Ice Age. More interestingly, when going deeper into the cave, scientists had to use a boat to move because they encountered an underground water layer, showing that this cave system has not been fully explored.
2. Mysterious Tunnel Under the Saxon Palace
During the renovation of the ruins of the Saxon Palace in Warsaw, Poland, archaeologists discovered a tunnel about 4m deep. What is special is that this tunnel is not included in any of the palace’s plans, showing that it used to be a secret passage. After much research, it was determined that this was a tunnel built by the Polish army in the 1930s for intelligence purposes during World War II.
3. Mysterious Tunnel System in San Francisco
San Francisco is home to many abandoned tunnels, and over the years, they have become the focus of mysterious stories. Photographer Sierra Hartman, who has a passion for urban exploration, has taken many photos of the dark passages under the city.
These tunnels are not only mysterious passages but also play an important role in the city’s drainage system. If not properly maintained, they can cause terrible environmental and health disasters.
4. Nazi Tunnels
During World War II, the Nazis built many secret tunnel systems to hide and hide important documents. One of them was the underground tunnel system in Bavaria, which was used as a final refuge for the regime’s leaders. These tunnels still exist today, carrying haunting historical stories.
5. The Bone Tunnels of Paris
The Paris Catacombs are one of the most creepy places in the world, containing the remains of more than 6 million people. These underground passageways were originally built to solve the city’s cemetery overcrowding problem in the 18th century. Today, some sections of the tunnels are open to visitors, but there are also mysterious areas that only the most adventurous dare to enter.
