As globalisation expands and airline companies proliferate, seeing the world has never been cheaper. But then again, not even billions could allow you access to these ten places. From top-secret factories to deserted islands, few will be visiting them anytime soon.
Here are ten places that most people will never be able to visit.
1. Coca-Cola Recipe Vault, Georgia, USA
Recipes are always personal to those who come up with them, but for a drinks company that generates billions each year, safeguarding a winning formula can mean hiding it in a steel vault.
In 2011, the most famous recipe in the world was transferred from its original vault at SunTrust Bank a few minutes up the road to the new World of Coca-Cola exhibit in Atlanta, Georgia. Monitored 24 hours a day, the majority of the vault's interior is heavily guarded, ensuring only top-level Coca-Cola executives access.
2. Area 51, Nevada, USA
Shrouded in secrecy, Area 51 is also fiercely guarded, which is probably why conspiracy theorists believe the base is more than just a testing ground.
Whatever you believe, chances are you won't be able to find out what's truly behind closed doors due to armed guards surrounding the entrances. And for those daring to go beyond the limits, you won't get very far. Just ask this guy.
3. Surtsey, Iceland
Potentially one of the youngest drylands on Earth, Surtsey in Iceland was only formed in the late 1960s following a volcanic explosion.
Thus, the rural and pristine nature of the largely untouched island has no doubt drawn attention across the world but only a few scientists have ever been allowed to explore it.
4. Bank of England Vaults, London
Guarded within an inch of its life, those wanting to immerse themselves in a room full of gleaming gold bars can only do so with a 90cm long key.
Don't have one? Well, tracking down someone who does will prove difficult considering employees names are kept secret.
5. The Mariana Trench, western Pacific Ocean
The Mariana Trench is the deepest part of the world's ocean, with an estimated depth of 10,994 meters.
Only three people have ever successfully reached the bottom. All others who have tried failed to return to the surface.
6. Pripyat, Ukraine
Chernobyl, along with the nuclear disaster in Fukushima, Japan, remains the worse nuclear disaster in recorded human history. 31 people lost their lives while countless others suffered long-term defects from the radioactive particles that spread over vast swathes of Eastern Europe. Resultantly and almost expectedly, the town soon became nothing but a mirage of lost objects, broken homes and empty stretches of desolate wasteland.
The city of Pripyat- where the nuclear power plant was based- is strictly prohibited by armed guards, with only those with special permission allowed access so long as an armed guard accompanies them.
7. Woomera Prohibited Area, Australia
As the name suggests, the world's largest weapons testing site, Woomera, is strictly prohibited.
And yes, that applies to daredevils too. And idiots.
8. Vatican Secret Archives, Italy
While Dan Brown and a host of conspiracy theorists/authors will tell you the Vatican is a hotbed of secrets, the 'Secret Archives' aren't that secret at all.
In fact, you can view any document that is older than 75 years old free of charge. Just don't expect to be granted access to any of the rooms.
9. Room 39, North Korea
While North Korea lets people into their nation on specially arranged tours, those wanting to explore anything other than what's on offer risk a long spell in a hard labour camp.
One such place no one with any sense should ever attempt to visit is Room 39. The secretive government facility is thought to be a place where a string of illegal operations takes place; including international insurance fraud and counterfeiting.
10. Ise Grand Shrine, Japan
Dating back to 4BC, only priests and priestesses of the royal family are allowed access to the shrine, which is rebuilt every 20 years following the Shinto idea of death and rebirth.
A fascinating place to visit.... if you can somehow gain access.