Coca-Cola’s recipe is perhaps the most famous trade secret in history. It now resides in an extraordinary vault that doubles as a tourist attraction. Company legend has it that only a tiny band of people knows the recipe. In December 2011, a metal box believed to contain the recipe was placed into a newly constructed 6.6-foot-high steel vault, which is not to be opened. The area is kept under constant surveillance.

Area 51 is a nickname for a military base located in southern Nevada in the western United States. Its primary purpose is to support development and testing of experimental aircraft and weapons systems. The U.S. government barely acknowledges the existence of this base, which makes it the frequent subject of conspiracy theories and a central component to UFO folklore. Needless to say, no trespassing is allowed.

There is one place in Disneyland that is always open to selling alcoholic beverages: Club 33. This private club is located in the heart of Disneyland’s New Orleans Square. Though the entrance to this secret club is relatively easy to find, to enter it you have to go to the end of a fourteen-year waiting list and be ready to pay a membership fee ranging between $10 and $30 thousand dollars.

Despite their names, the archives are not actually secret; you can view any document you wish. The only documents one cannot access are those which are not yet 75 years old. However, no one is allowed inside the vault itself. You need to submit your request for a document and it will be supplied to you. The Vatican Secret Archives have been estimated to contain 52 miles of shelving and 35,000 volumes in the selective catalogue alone.

This closed Russian town is believed to house people working on the highly secret Mount Yamantaw. Mount Yamantaw stands at 5,381 feet and is the highest mountain in the southern Urals. The area is believed to be a large, secret, nuclear facility and/or bunker. In response to U.S. questions regarding the site, the Russian government said it is a mining site, a repository for Russian treasures, a food storage area, and a bunker for leaders in case of nuclear war.

This exclusive English gentlemen’s club was founded in 1693 by Italian Francesco Bianco, who intended to sell the newly discovered drink called hot chocolate. Eventually it became an extremely private gentlemen’s club. Men who want to join this exclusive club can only do so if invited by a sitting member supported by two other members. Therefore, for the vast majority of people this is a place they will never get to see.

Metro-2 in Moscow, Russia is a purported secret underground metro system. It was supposedly built about 60 years ago and it parallels the public Moscow Metro. Russian journalists have reported that the existence of Metro-2 is neither confirmed nor denied by local authorities. It is rumored to connect the Kremlin with the FSB headquarters, the government airport at Vnukovo-2, and several other locations of national importance. The fact that its existence has not yet been publicly confirmed makes it more than hard to visit.

Room 39 was established in the late 1970s and is arguably one of the most secretive organizations in North Korea. It has been described as the lynchpin of the North’s so-called “court economy.” It is widely speculated that the organization uses 10 to 20 bank accounts in China and Switzerland for the purposes of counterfeiting, money laundering, and other illicit transactions. However, very little reliable information is known about Room 39 due to the secretive nature of the organization.

The Ise Grand Shrine in Japan is dedicated to Amaterasu, the sun goddess, and has been in existence since 4 BC. The main shrine is said to hold the most important item in Japan’s imperial history, the mirror from Japanese mythology which eventually ended up in the hands of the first emperors. The reason this shrine has entered the list is simple: the only person who can enter is the priest or priestess, who must also be a member of the Japanese imperial family. This means that unless you are a member of Japanese royalty, you will never get to see this mirror.

RAF Menwith Hill is a British military base which also acts as a ground station for a number of satellites operated by the U.S. National Reconnaissance Office on behalf of the U.S. National Security Agency. It has been described as the largest electronic monitoring station in the world, containing an extensive satellite ground station. RAF Menwith Hill is alleged to be an element of the ECHELON system, which was reportedly created to monitor the military and diplomatic communications of the Soviet Union and its Eastern Bloc allies during the Cold War in the early 1960s. It is also believed to filter all telephone and radio communications in the nations which host it.

The Mount Weather Emergency Operations Center was set up in the 1950s due to the Cold War, but it continues to operate today. It is what some call a “last hope” area, a highly classified place where U.S. government officials and a chosen few get to go in the hopes that they can escape the kind of impending doom seen in most modern “end of the world” movies. The center is already functioning with extensive telecommunications traffic routed through it.

Since 1734, the central bank of the United Kingdom has been based at Threadneedle Street in the heart of the City of London. The underground vaults located beneath the bank’s floors store not only the gold reserves of the UK, but also the wealth of countless other countries. Access to the vault these days is via huge doors that are opened by 3-foot-long keys. The identity of staff who work in the vaults is a closely guarded secret.

This is the legendary tomb of China’s first emperor. Chinese authorities have so far resisted all requests made by academic teams wishing to excavate the main tomb area. For the foreseeable future at least, it seems Qin Shi Huang will rest in peace.

Google’s enormous Data Center at The Dalles was built amid great secrecy at a cost of $600 million. The Data Center, codenamed “Project 02” in its early days, opened in 2006. Even its opening was shrouded in secrecy; all visiting journalists were required to sign confidentiality agreements. The Center itself is surrounded by a perimeter fence that is patrolled by guards and is constantly under closed-circuit surveillance. The Internet may be the one place where all information is easily accessible, but Google clearly prefers to keep the information on its data centers secret.

Snake Island, located just off the coast of Brazil, is home to a vast colony of golden lancehead pit vipers. This species is among the most poisonous snakes on the planet. The Brazilian Navy expressly forbids civilians from landing on the island, and for a good reason: there are at least 5,000 snakes writhing around the place. Without any doubt, this is an ophiophobe’s vision of hell with snakes wandering all over the island. Only scientists are allowed to enter this secret serpentine paradise.