15 Underground Sites That Offer A Glimpse Into The Past

The world beneath our feet holds more than just rock and soil—it hides entire civilizations and secret tunnels that once sheltered thousands. Time has changed these underground spaces into eerie and mysterious landforms where the echoes of history still whisper through the darkness. Keep reading to discover 15 underground sites that are gateways to an unsettling world.

Catacombs Of Paris, France

Beneath Paris lies a network of tunnels called the Catacombs, which hold the bones of over six million people. Originally limestone quarries, they were repurposed in the 18th century due to overcrowded cemeteries. Only a small portion of the Catacombs is legally accessible. Still, some explorers, known as cataphiles, tour the forbidden sections.

Derinkuyu Underground City, Turkey

Hidden beneath Cappadocia is an ancient underground city reaching depths of 200 feet. It was likely built during the Byzantine period (5th to 10th centuries CE) and could house up to 20,000 people. Designed for defense, Derinkuyu features massive stone doors sealing off tunnels from invaders. Despite its brilliance, the dark, twisting passageways create a claustrophobic atmosphere.

Edinburgh Vaults, Scotland

Edinburgh’s South Bridge sits on the Edinburgh Vaults, a network of dark chambers built in the 18th century. Though initially used for businesses and storage, they became slums and a haven for criminals, illegal gambling, and even body snatchers. The vaults were eventually abandoned and ignored for nearly 200 years before being rediscovered in the 1980s.

Shanghai Tunnels, USA

These tunnels were constructed beneath Portland, Oregon, in the 19th century and were used for transporting goods. However, criminals, known as Shanghaiers, also used it to kidnap men and force them into slavery. Many victims never escaped, and some are believed to have died within the tunnels. Today, visitors report ghostly figures lurking in the dark.

Odessa Catacombs, Ukraine

The Odessa Catacombs form a maze of about 1,500 miles of underground tunnels, originally used as limestone quarries. Over time, they became hideouts for criminals and also resistance fighters during WWII. These tunnels are so vast that people have gone missing.

Orda Cave, Russia

The Orda Cave in Russia is the world’s longest underwater gypsum cave, stretching over three miles beneath the Ural Mountains. Its crystal-clear water provides almost unlimited visibility, making divers feel like they are floating through a glass-like alien world. The cave’s white gypsum walls give it a glowing appearance, creating an illusion of endless space. 

Berlin Unterwelten, Germany

Berlin sits atop the Unterwelten, a series of underground bunkers and tunnels constructed during WWII. These dark corridors were used as air-raid shelters and escape routes for soldiers and civilians. Today, Berlin Unterwelten e.V., an organization dedicated to preserving and researching these spaces, offers tours exploring the city’s hidden history.

Ploutonion At Hierapolis, Turkey

Known as the “Gate to Hell,” the Ploutonion was an ancient temple in Hierapolis believed to be an entrance to the underworld. The site emits toxic fumes from a natural geothermal vent, which the ancients thought were the breath of Hades. Scientists have confirmed that the carbon dioxide levels in the chamber can asphyxiate anything.

Moaning Cavern, USA

This massive underground chamber in Vallecito, California, is known for its eerie moaning sounds caused by air moving through its narrow passages. The cavern has a dark past, as ancient human remains—some over 12,000 years old—have been discovered at its depths, leading to theories that it was used for burial or ritualistic purposes.

Chislehurst Caves, England

The Chislehurst Caves in Kent, England, are a vast network of artificial tunnels. First dug by the Celts and Romans for chalk and flint mining, the caves later served various purposes. Some claim the caves have a portal-like energy, making them a hotspot for supernatural encounters. The twisting tunnels create a feeling of isolation and dread.

Gilmerton Cove, Scotland

Gilmerton Cove is a mysterious underground network of hand-carved tunnels and chambers beneath Gilmerton in Edinburgh, Scotland. Believed to date back several centuries, its origins and purpose remain largely unknown, with theories suggesting it was used by secret societies or smugglers. The passageways include stone benches, a well, and even what appears to be a table.

Napoli Sotterranea, Italy

Naples has an underground city called Napoli Sotterranea. The Greeks first carved it out as tunnels for aqueducts; then the Romans expanded it.  During WWII, they served as bomb shelters, protecting thousands of civilians from air raids. They are now filled with eerie remnants of their past, including graffiti from wartime refugees and forgotten staircases.

The Wieliczka Salt Mine, Poland

Featuring vast tunnels and sculptures carved from salt, the Wieliczka Salt Mine is one of the most surreal underground locations in the world. This 13th-century mine, which descends over 1,000 feet underground, has an eerie atmosphere. The mine’s many dark corridors, illuminated only by dim lighting, feel like something out of another dimension.

The Reed Flute Cave, China

China’s Reed Flute Cave is a breathtaking underground world illuminated by colorful artificial lights, making it look like a fantasy dreamscape. Formed over 180 million years ago, the cave is filled with towering stalactites, stalagmites, and mirrored pools. Ancient inscriptions dating back over 1,000 years are also carved into the walls.

The Waitomo Glowworm Caves, New Zealand

One of the world’s most magical underground locations, New Zealand’s Waitomo Glowworm Caves are illuminated by thousands of bioluminescent glowworms. These creatures emit a blue-green light, creating the illusion of a starry sky inside the cave. As visitors drift along the underground river, the glowworms form an ethereal canopy above.