Area 51: Nevada's top-secret air base is heavily guarded, and no one is allowed to enter or even fly over the area. The area is believed to be the site used by the United States to secretly develop and test new Air Force aircraft, and the place is also famous for what many believe it is associated with numerous UFOs.
Rio Federal Reserve Bank: About 25 percent of the world's gold is stored here, so much money needs to be protected no wonder it's so cautious, the repository is 80 feet underground (about 24 meters) below sea level, and the buildings around the perimeter are guarded by trained snipers
Fort Knox: The highly guarded Fort Knox is where the U.S. Treasury's gold is stored, not only storing tens of millions of tons of gold, but also important historical documents, such as the Declaration of Independence during World War II, the Magna Carta, which had seven power grid maintenance, heavily armed security guards, and a twenty-four-ton security gate.
Tumen River: The boundary river between China and North Korea, the lower reaches of the border between Russia and North Korea, in 1.6 kilometers you can cross China from North Korea to Russia, so that many escaped refugees cross the river into China in this section of the border
North Korean Military Zone: Commonly known as the "March 8th Line," the North Korean Demilitarized Zone is a narrow strip of land that borders North and South Korea, and is also the border between the world's most military personnel. It is 257 km long and 4 km wide.
Principality of Sealand: a state proclaimed by an individual but not universally recognized internationally, located on a small island in the English Channel, which has been occupied since its inception by its head of State: Paddy Roy Bates and his family and partners.
Green Rose Resort: This unique resort, 6,500 acres deep in the forests of West Virginia, yet he is really secretly underground, where a 25-ton blast gate is hidden. Supplies and food were always available in the bunker.
Cheyenne Hill Military Base: The most heavily guarded cave military base in the world. Because the Cheyenne Hill military base is located deep in the North American continent and easy to hide, in May 1958 the United States and Canada decided to jointly establish the North American Air Defense and Anti-Air Defense Command.
Mysterious Mormon Church: Mormon Church does not allow outsiders to enter, only outside to see, they are not only heavily guarded but also infrared surveillance equipment
Bold Lane Car Park: Here you don't have to worry about someone stealing your car, this humble car park in derby, central England, is the safest place in the world. The parking lot uses a complex network that includes CCTV system camera emergency buttons, multi-level entrances, and barcoded tickets.