Whether they’re real or fictional, the idea of subterranean cities on this planet is both a romantic notion and an unnerving one at the same time. While stories like Jules Verne’s Journey to the Center of the Earth may seem fantastic with its notions of what lies beneath the Earth’s surface such as an underground ocean or a forest covered in giant mushrooms, it was partially based on theories about the planet’s inner-workings that were prevalent at the time of the novel’s release which was the early 1800s. But while those theories have certainly changed since then, that didn’t stop all kinds of pulp stories from being written about explorers stumbling upon subterranean kingdoms and subsequent movies from being made including Atlantis: The Lost Empire under the umbrella term “Subterranean Fiction”.

However, there are also real-life subterranean cities with some being made thousands of years ago to shelter people during times of heavy warfare or to prepare for possible events like prohibition and the like. Some of them even had darker purposes, making them less appealing to go to even though they’re not in use anymore. Plus, the subterranean nature of these places has caused parts of them to collapse over the years making them nearly inaccessible. So here’s a list of underground cities one would be most likely to avoid along with a few that might be worth checking out after all.

25 Xibalba - Place of Fear

Just as the Ancient Greeks believed in the Underworld as the place where human souls go to after passing on, the Mayans had their equivalent in the form of Xibalba. Ruled by various gods who were believed to cause various illnesses, this mythical place was said to be full of traps and trials that would throw off any wanderers keeping them in Xibalba indefinitely. Although according to The Guardian, it was believed that the entrance to Xibalba could be accessed through a series of caves in places like “Guatemala, Mexico and Belize” though it’s unlikely that Xibalba itself is real.

24 Jurong Rock Caverns - Great Workplace

So instead of an office, how about working in a series of caverns for a change? Sounds pretty far-fetched, right? Such is not the case for the scientists that are housed in the caverns near Jurong, Singapore. Artificially created by the Jurong Town Corporation (or JTC for short), these caverns not only store tons of “Oil and gas” as reported by The Guardian but they also house the scientists who work there on a daily basis. While it is the first facility of its kind in Southeast Asia, according to The Straits Times, it’s not Singapore's first underground venture.

23 Lalibela - Sacred Rock

In the country of Ethiopia, there resides this unique village which is known for its partially subterranean churches. Constructed in the Twelfth century, HISTORY states, they were built from the inside of volcanic rocks that were below ground and gradually hollowed out. The most famous one of these churches is the Church of Saint George (as shown in the above picture). Resting in a deep trench, this church was carved from a large monolithic stone into the cross-shaped building it is today. On top of that, the church connects to an entire underground network of tunnels beneath the village.

22 City of the Gods - Ancient Mysteries

Supposedly located in Egypt, this place is said to lie directly beneath the Pyramids of Giza. According to Culture Trip, notions of such a city weren’t researched until the 1970s leading to the name and subsequent mappings of the place which so far consists of “Chambers and tunnels”. Though an article on Ancient Code claims that many ancient philosophers including Herodotus had written about underground tunnels connecting the pyramids, this doesn’t exactly prove there’s an actual city beneath them. Yet recently, an underwater expedition by archeologists revealed signs of the forgotten city of Heracleion/Thonis as stated by Atlas Obscura.

21 Shanghai Tunnels - Carried Off

Beneath Portland, Oregon, lie a series of underground tunnels connecting the old part of town and the downtown area. But where their name comes from is that Portland’s Old Town was also called Chinatown, and it was rumored that shanghaiing incidents happened here. Because these tunnels connect to the waterfront, supplies could easily be brought from the ships to the basements of various businesses in Old Town as stated by momondo. So the Shanghai Tunnels seemed like the perfect place to make someone join a ship’s crew against their will, although there’s not enough evidence to suggest this really happened.

20 Setenil de las Bodegas - Built into the Cliff

Unlike the other places that have been covered thus far, this one is technically built into the side of a cliff (as opposed to being underground) located in the southern part of Spain. With that said, though, many of the houses actually reside in the cliff and beneath the cliff’s overhanging rocks (as shown above). The reason they were built this way, according to momondo, was so the residents could not only be sheltered from the heat during the summer but also remain warm during the winter due to the natural shielding of the cliff itself against the cold winds.

19 Orvieto Underground - Etruscan Secret

In the city of Orvieto, Italy, which rests on volcanic rock, there lie a series of hidden underground tunnels and chambers. Originally built by the Etruscans, who were the native people of Italy during the time of the Ancient Greeks, these tunnels were mainly used to store various things including “Medieval olive presses” as well as “Roosts for pigeons” HISTORY says. The tunnels also served as makeshift shelters during times of war. This even continued all the way up to WWII, HISTORY states, although nowadays they mainly serve as a tourist attraction and designated location for certain events.

18 Sonnenburg Shelter - Not Working Right

Next to the Sonnenburg motorway tunnel that was built in the 70s lies a hidden shelter of the same name that was made a decade earlier in the city of Lucerne, Switzerland. Its purpose, The Guardian states, was to provide a place for the city’s residents to go to in case of a nuclear event in wake of the Cold War resulting in Swiss laws that dictated everyone should have access to a fallout shelter. Yet in the years that followed, it turned out parts of the facility didn’t work including the blast doors so the whole project was abandoned.

17 Burlington Bunker - Be Prepared

On a similar note, Britain was also concerned about the possibility of an upset. So to protect their most important members of government, as stated by HISTORY, they constructed a special bunker in the 50s under Corsham, a small town just north of Bath. Made from preexisting tunnels, the Burlington Bunker consisted of a telephone operating system (such as the one shown above) to keep the government members in communication with the outside world as well as living quarters for them to stay in. Though not fully utilized, HISTORY says, the bunker’s facilities were partially used until the early 2000s.

16 Vicksburg Caves - Southerners in Danger

Towards the end of the Civil War, a town in Mississippi called Vicksburg was under siege by Yankees from the Northern states. While the town was heavily fortified, there was only so much the other side could defend. So to protect themselves, the remaining residents of Vicksburg built a series of caves as stated by The Guardian to wait things out. However, once the Yankees started using shells to damage the town itself the residents were practically trapped inside the caves. On top of that, a dozen casualties were accounted for before the town peacefully surrendered to the Yankees.

15 Edinburgh Vaults - Poor Unfortunate Souls

Also called the South Bridge Vaults, this place dates back to the late 1700s and primarily consists of tunnels built into arches. According to momondo, the vaults were made to house a variety of businesses including “Taverns, cobblers, cutlers, smelters” and to store things that were apparently illegal. This event included the victims of two men named Burke and Hare who would temporarily store them in the vaults before taking them to a local doctor to be used for science. Later, the tradesmen left and the vaults housed all sorts of riffraff who would come down to get rowdy.

14 Tunnels of Moose Jaw - Bootleg Network

Located in the southern part of Canada, this small town has tunnels of its own that have become famous due to their dark history. In the early Twentieth century, momondo states, they were occupied by Chinese immigrants who had nowhere else to go due to the large amount they had to pay for a tax that was specifically targeted at them for political reasons forcing them to live below ground. Then later, the tunnels were used to illegally transport booze during the 20s which was supposedly run by Al Capone himself despite the lack of evidence as stated by momondo.

13 Dixia Cheng - Fallout Paradise

While Britain was mainly concerned about protecting its government members, and Switzerland thought about the safety of everyone, China had a more ambitious goal when constructing its own fallout shelter. Built beneath the city of Beijing, according to HISTORY, this place was designed to not only house “One million people” but it also included many other large facilities including schools a movie theater and skating rink. Like the other previously mentioned fallout shelters, Dixia Cheng wasn’t used to its full potential either with most of it sealed off now due to the large amount of decay.

12 Bunkers of Berlin - Reminder of the Past

As WWII was coming to an end, the city of Berlin was being subjected to multiple air raids by the Allies which included America and Britain. So the city’s inhabitants would seek shelter in these underground bunkers that were constructed beneath in order to wait for the allied planes to pass over and allow them to return above ground once the raid had ended. However, Germany’s leader had an ulterior reason for building the bunkers. As The Guardian states, he was planning to create an entirely new city from the ashes of Berlin called Germania which never happened.

11 Derinkuyu - Hollow City

Located in the Cappadocia, a semi-arid desert in Turkey filled with chimney-shaped rock formations, this underground city is actually one of many but it’s the most famous due to its complex network and sophisticated structures. Not only was this place built to house people during wartimes as early as the Eighth century, according to HISTORY, but it was also a fully functioning city with various facilities and living spaces that would be big enough to accommodate approximately 20,000 people. Apart from ancient groups such as the Hittites, the city was also used by Christians from the Byzantine Empire.

10 Naours - Shelter for the Soldiers

Inside a plateau in the northern part of France, this place resides having served many purposes in its long centuries' worth of history. Starting in the Third century, HISTORY states, it was “Part of a Roman quarry” initially before ultimately transforming into an underground village that was used to shelter people when wars happened. This was especially the case in the Middle Ages, before being sealed off until the Nineteenth century. Though it was a tourist attraction back then (as it is now ironically), the caves also happened to shelter soldiers who fought during WWI according to HISTORY.

9 SubTropolis - Underground Mushroom Farm (Maybe)

While it’s not an underground city in the technical sense, it’s still a large subterranean place that has an interesting history behind it. Built under Kansas City, Missouri, it’s essentially a large storage facility that’s said to be the biggest in the world according to The Guardian. Kept at cool temperatures, it’s used to store everything from stamps collected by the United States Postal Service to limestone that’s extracted for different uses around the region. In fact, various companies are even planning to use SubTropolis as a place to farm mushrooms as well as “Store crude oil” says The Guardian.

8 Coober Pedy - Mining and Dining

Considered to be the Opal Capital of the World, according to Culture Trip, this unique town in southern part of Australia not only has underground mines where workers collect the precious gemstone in its raw form but also living spaces known as “Dugouts”. The purpose of the latter is to help the town’s residents deal with the intense heat that’s present in the region leading to the rise in other underground facilities besides homes such as restaurants and churches. Also, Culture Trip claims the dugouts help protect the citizens from the area’s resident dingos by giving them someplace to hide.

7 Wieliczka Salt Mine - Everything That Glitters

Dating back to the early Middle Ages, this underground complex was built outside of Krakow, Poland, after rock salt had been found here. While the mining continued for centuries to come, the workers used the leftover materials to build all kinds of things including chapels like the one in the above picture. Hence, the place eventually came to be called the “Underground Salt Cathedral,” HISTORY says. Though the rock salt mining eventually ended, lots of tourists flock to the place to not only see the surprisingly grandiose architecture but also for an underground health spa that is present as well.

6 Pilsen Historical Underground - Fancy Storage-Room

Located under the city of the same name in the Czech Republic, this maze of cellars was also built in the Middle Ages but a couple centuries later than the Wieliczka Salt Mine. The reason they were built was primarily to store excess food and barrels of brew. But it is rumored these tunnels might have been used “As an escape route,” according to HISTORY, in times of war and there’s possibly buried treasure. Nowadays, though, there are guided tours throughout the place ending at a museum where one can sample the special brew this city became known for making.