We're used to hearing a lot of interesting things about the places that we can visit. And when a location fascinates us, we think, "Oh, that's cool! I should add this place to my Bucket List and visit it someday!". But what about the places that we can decidedly leave off our Bucket Lists? What about those forbidden locations we aren't allowed to enter?

It's hard to imagine that there are such places in our world, yet there are a number of them. To name a few, there are military bases that want only their staff members to access. There are historical sites that are so fragile that they can be seriously damaged by the human presence. And there are also dangerous places that none of us would ever want to visit. Yet many of these places intrigue us, like a forbidden fruit that immediately becomes so desirable. They attract some curious travelers like magnets, making them strive to explore the unknown lands. And still, it's better not to even try to visit these places, for the sake of your own life.

UPDATE: 2022/07/05 15:53 EST BY KATHIA BELLO

Mysterious or forbidden places have capture the imaginations of travel lovers for centuries. As such, we have updated some of the info and resources on this article to reflect their ever present fascinating histories.

So let's take a look at some of the most interesting places in the world that people can't (legally) visit unless they are researchers, scientists, military men, or daredevils.

20 Vatican Secret Archive, Vatican

The Vatican Secret Archive, known as the Vatican Apostolic Archive since 2019 serve as a storage space for numerous documents relating to the Catholic Church. Some of these documents date as far back as the 8th century. Among others, there is said to be papal account books, a letter from Michelangelo to Pope Julius II, a letter from Mary Queen of Scots written before her execution, and Martin Luther's excommunication document.

Most of the archive is located underground, and it has 85 kilometers (53 miles) of shelves. It's forbidden to enter it for anyone, except for researchers with special permits to access. But even for them, there are multiple limitations to what documents they can view.

19 North Brother Island, New York, USA

Located in New York City's East River, in between Bronx and Riker's Island, North Brother Island is a 13-acre piece of land that became the last refuge to over one thousand people, whose passenger ship sank in its waters. Later it became home to a hospital for people with contagious diseases. The most well-known resident of it was Mary Mallon, aka Typhoid Mary. She was the first documented person in the country to have typhoid fever, and it's estimated that she infected over 50 people with it, 3 of whom passed.

Now the island is abandoned, and it's home to a bird sanctuary and off-limits to the public, though special access for scientific purposes can be granted.

18 Bhangarh Fort, Rajasthan, India

Technically, the Bhangarh Fort isn't completely banned to access, because tourists can visit it in the daylight and see this marvelous example of Rajasthani architecture. However, from sunset to sunrise, there is a strict ban to enter this place. Generally regarded as the "most haunted place in India", this 16th-century fort is full of legends about ghosts and curses. Hearing some of them will certainly send shivers down your spine.

You might be wondering what happens to those who dare to visit the Bhangarh Fort at night. In fact, no one knows, because, according to locals, whoever tried to break the rule mysteriously disappeared after it.

17 Heard And McDonald Island, Australia

One of the most remote territories in the world, Heard Island is considered an Australian territory, even though it's located between Madagascar and Antarctica. It's home to a wide range of animals, such as seals, penguins, and marine birds, as well as more than 40 glaciers.

There were a few reasons for closing the island to public. First, in 2000, researchers noticed a huge lava flow coming from the island's massive volcano called Mawson's Peak. Second, Heard Island is known for its poor weather conditions. And third, it's too remote to be safe. Judge it by yourself - it's located in a minimum two-week sail to the closest major landmass.

16 Lascaux Caves, France

Not all UNESCO World Heritage sites are open to the public. For example, the Lascaux Caves in France, which feature invaluable cave art thought to date back 17,000 years ago, have been banned to enter since 1963; that is because they were threatened by a series of fungal invasions due to a large number of visitors. This occasion revealed that any human presence is destructive to the caves. So to preserve 900 examples of prehistoric art dating back to the Paleolithic era, tourists can't come in there anymore, but replicas have been put in place for public viewing.

Related: Here’s The Story Of The Island Of The Dolls, And Why People Go To Mexico Just To Visit

15 Ilha Da Queimada Grande, Brazil

Better known as Snake Island, Ilha da Queimada Grande is home to a huge population of snakes. According to some estimates, there's one snake in each square meter of the island. And they aren't just some harmless grass snakes that only frighten you with their look but can't cause you any damage. The snakes living in this island are world's most dangerous species. Among them is the golden lancehead viper whose venom melts flesh around the bite. Yikes!

So it's logical why the Brazilian government closed the island for visitors. Only qualified researchers from or authorized by ICMBio (Chico Mendes Institute of Biodiversity Conservation), who know how to deal with snakes, and can only enter under the condition that they have a doctor in their team.

14 Area 51, Nevada, USA

Area 51 isn't only one of the most well-known forbidden places in the United States, it's also one of the most mysterious locations in the US. According to many of them, an alien spaceship crashed there, while according to others authorities use this place to examine the spaceship that, allegedly, crashed in Roswell, New Mexico (another super-mysterious place).

The official version states that Area 51 is the site used by the U.S. Air Force and CIA as a testing territory due to its remote location. If it's true (and it probably is), it's logical why the place is banned to enter for public.

13 Pravcicka Brana, Czech Republic

Europe's largest natural sandstone arch, Pravcicka Brana is one of the most well-known attractions of the Czech Republic. Well, at least it used to be until 1982, because in that year it was forbidden to visit for tourists. The reason of the ban is simple: the more visitors come to the area, the more likely it is to collapse one day. So to reduce erosion of this beautiful landmark, tourists can now see it from afar, but not climb onto it.

Unfortunately, the erosion process continues even without "the help" of visitors and, according to geologists, the arch can still collapse in the future. But at least the ban decelerates the process and gives us more time to admire it.

12 Morgan Island, South Carolina, USA

A colony of approximately 4 thousand rhesus monkeys lives on Morgan Island, South Carolina, due to which it was nicknamed as Monkey Island. But, despite what you might think, the population of primates isn't native to the island. They were relocated there from Puerto Rico due to the spreading of herpes virus B infection. Before it happened, the island was uninhabited.

These days, people are prohibited by law to visit the island for their own safety, as well as for the safety of the monkeys. Only a handful of researchers from the National Institute of Allergy and Infectious Diseases (NIAID) can go there.

11 Mausoleum Of Qin Shi Huang, China

Although the tomb of Emperor Qin Shi Huang was discovered upon unearthing the Terracotta Army in 1974, it hasn't been excavated yet. According to the opponents of excavation of the tomb, modern technologies can't prevent its destruction. For this reason, the access to it is still forbidden by the Chinese government that strives to preserve their cultural heritage and pays respect to the man buried there.

All we know about the mausoleum now is that it consists of a complex network of caverns underground, filled with the objects that, according to those who buried him, the emperor could have needed in the afterlife. Among others, it holds the reproduction of his army, known as the Terracotta Army, made of clay.

Related: Plum Island: The Truth Behind The 'Area 51' Of The East Coast

10 Svalbard Global Seed Vault, Norway

Sometimes referred to as "the Doomsday Vault", the Global Seed Vault in Norway is actually a very important place for all of us. It stores 100 million seeds from all over the world to restore the plant kingdom in case something really, really bad happens to our planet's vegetation. Opened in 2008, the vault was built to last about 200 years and it can withstand explosions and earthquakes. Besides, since it was placed on the side of a mountain, it will still be above sea level, even if all ice on the planet melts.

It's interesting that the vault knows no politics: even North Korea has given its seeds for storage there.

9 North Sentinel Island, India

North Sentinel Island is a small landmass in the Bay of Bengal. Its indigenous population, known as the Sentinelese, rejects any contact with the outside world and remains one of the few peoples that remain untouched by our civilization. How do they keep outsiders away from their island? They simply shoot arrows at them. For this reason, it's impossible to approach the island and survive the encounter.

Here's an interesting fact: when researchers were assessing the damage after the 2004 Indian Ocean tsunami, even their helicopters were attacked by the Sentinelese for approaching the island. None of them were hurt, of course, but this example shows how fiercely the island's population is protecting their territory.

8 Mezhgorye, Russia

Being the largest country in the world, Russia is certainly full of surprises. It has a lot of mysterious sites, ghost towns, and other special places. Like, for example, Mezhgorya in the Republic of Bashkortostan. It's a closed town hidden somewhere in the Southern Ural Mountains. To keep off anyone who wants to penetrate into the town or even come close to it, it's encircled by two battalions.

It's not 100% clear that this area is and why it's surrounded by this kind of secrecy. According the most believable reports, it's a nuclear missile site that allegedly has automatic missiles that can be controlled remotely. But, since government officials don't comment anything on it, we still can't be sure what Mezhgorya is.

7 Grand Shrine Of Ise, Japan

The Grand Shrine of Ise in Japan is a very important place for the Shinto religion, because it was built to honor Amaterasu, a goddess of the sun and the universe. Interestingly, the Inner Shrine, Naiku, was constructed without a single nail. Even more interestingly, this temple is rebuilt every 20 years, according to the Shinto idea of death and rebirth (most recently, it took place in 2013). And every time they reconstruct the shrine anew, they keep on using the wood joining technique and never utilize nails.

To keep the place holy, only priests and members of the imperial family of Japan can go there. Everyone else can gaze at the temple from the outside, through wooden fences.

6 Surtsey, Iceland

Surtsey, one of the youngest islands in the world, appeared due to a volcanic eruption that lasted from 1963 to 1967. These days, it is only used for scientific purposes. Any visitors, except for research groups, are forbidden to visit this island, because on its example scientists want to understand how ecosystems form without any human influence.

One of the main rules for the scientists was to avoid bringing any seeds to the island. However, some of them disregarded it and brought tomato seeds there in their own colon (in other words, someone pooped there and a tomato plant sprouted up). As soon as scientists realized the origin of this plant, they removed it to continue their spotless research.

Related: Toniná: Guide To Mexico’s Lesser-Visited Mayan Ruins

5 Chichen Itza Pyramid, Mexico

You might be surprised to see Chichen Itza in this list, because it's considered one of the most popular tourist attractions in the world. And you're right about it - millions of tourists come to this site every year to marvel at the beautiful Mayan pyramid. However, even though you can come there, since recently it's strictly forbidden to climb it.

The ban was issued after a woman tumbled off the pyramid on her descent in 2006. This event had a tragic ending and, to avoid anything similar from happening in the future, it became closed to the public to the disappointment of multiple tourists, striving to reach the top of Chichen Itza.

4 Niihau Island, Hawaii, USA

Also known as the Forbidden Island, Niihau was purchased by Elizabeth Sinclair, a Scottish farmer and plantation owner, back in 1864 and since then it's privately owned by her descendants.

In 1952, the Hawaiian islands faced a polio epidemic and, as an attempt to avoid the spreading of the disease, a ban to leave or enter the island was issued. Luckily, no one got sick on Niihau and now it houses a population of only around 170 people. To enter it, one has to get a special permission, which is quite difficult not only for us, average people, but also for the rich and popular.

3 Poveglia, Italy

Poveglia is a small island located between Venice and Lido. In the past, it used to be a plague quarantine station and hosted more than 160 thousands infected people, who were living their last days and hours there. According to some reports, 50% of the island's soil consists of human remains. And, as if this tragedy wasn't enough, the island later became home to a mental hospital that had a very sinister reputation. After some time it was closed and now Poveglia is strictly forbidden to enter for anyone.

As if someone in their right mind would want to come to this creepy place...

2 Pluto’s Gate, Turkey

Back in the ancient times, people didn't dare to come into Pluto's Gate in Hierapolis, Turkey, because they believed it to be a very dangerous place. According to the ancient historian Strabo, no one could survive there. After visiting this place, he wrote that he "threw in sparrows and they immediately breathed their last and fell."

To everyone's surprise, Pluto Gate's reputation was confirmed by scientists in 1965. After measuring the CO2 concentration they found out that at night, when the temperature decreases and CO2 becomes heavier than air, it forms some kind of a lake on the bottom of the Gate. At dawn the concentration reaches its peak and any living being risks their life by getting there. However, at daytime the site becomes safer, because the sun dissipates the gas.

1 Fort Knox, Kentucky, USA

Being home to the bigger half of the U.S. gold reserves, the Fort Knox is frequently referred to as the most heavily guarded place in the world. It has quite a few security measures that can blow anyone's mind.

The most interesting thing is that even none of the staff members can have an access to the vault. To gain access to it, they need to know several combinations, but each staff member knows only one of them, so they can only enter the vault with the help of their colleagues. Besides, since the building is made of concrete-lined granite and reinforced by steel, it can withstand any attack from the outside world.