In 1940, 11-year-old Audrey Hepburn studied ballet in occupied Holland. To aid the resistance, the students performed in secret while Nazi patrols roamed nearby. Applause was forbidden, and later Hepburn said, "The best audience I ever had made not a single sound at the end of my performance."
2. When King Kamehameha of Hawaii died in 1819, his body was taken and buried in secret in accordance with Hawaiian tradition to preserve his mana. To this day, his body has not been found and people only speculate on its location.
3. A man created an armored bulldozer in secret and used it to revenge on a town before killing himself. It cost the town $7 million in damages.
4. Every ball used in an MLB game is covered in mud that comes from a secret location in New Jersey. A man skims through riverbanks to find the mud, then refines it before it's applied to balls. It's called the Lena Blackburne Original Baseball Rubbing Mud.
5. In 1977, William Kampiles stole a top-secret KH-11 spy satellite manual from the CIA which he sold to the Russians for $3000. He then told the CIA for whom he worked, what he had done, in the hopes that they would hire him as a double agent. They didn't and he was sentenced to 40 years in prison.
A secret radio belonging to a British POW in World War 2 was kept so well hidden that when he visited the camp 62 years later it was still there.
7. In 2004, the Parisian police in an uncharted area of the Paris Catacombs found a secret room with a stocked bar and restaurant. They returned to trace the installed power and phone lines to discover they had been cut, with a note left behind reading, "Do not try and find us."
8. Alan Rickman dated the same woman named Rima Horton for over 40 years. In 2012, he married her in a secret ceremony, then walked over the Brooklyn Bridge together. They didn't tell anybody until 2014.
9. KFC, in order to keep the original recipe a secret, has a company mix the first half of the 11 spices then ship it to McCormick, who adds the second half to the mix before sending it back to KFC.
10. A wanted robber known as "Roofman" (Jeffrey Allen Manchester) created a secret hideout inside a Toys "R" Us. He played with toys, watched DVDs, ate baby food, and installed a baby video monitor to keep an eye on the store.
In 1957, an explosion occurred at a plutonium plant in the USSR, resulting in the third worst nuclear accident in history. The government kept it secret for 19 years.
12. Billionaire Tom Perkins spelled out a secret message using nautical code flags strung along the length of his enormous yacht. The message? "Rarely does one have the privilege of witnessing vulgar ostentation displayed upon such a scale."
13. The 1997 video game "The Lost World: Jurassic Park", had a secret ending where Jeff Goldblum implored the gamer to stop playing computer games, go outside, talk to opposite sex and live their lives.
14. While at the toilet, president Carter hit a secret "panic button" thinking it was a flush toilet button and Secret Service responded by bursting into the room while the president was still zipping up his trousers.
15. The United Kingdom still retains 18 Queen's Messengers, who hand deliver secret documents to British embassies worldwide, traveling undercover in business class. The diplomatic package has its own "passport", as though it's a human being, and is exempt from being searched or x-rayed by airport security.
16North End tube station
The deepest London Underground station (North End tube station), 221 feet underground, was never completed and was used to store secret archives during World War 2.
17. The US Navy's most secretive naval base is located in a remote lake in northern Idaho. This base is believed to be used to develop stealth submarine technology and some locals believe that there is an underground waterway to the Pacific ocean used for top-secret deployment
18. South Korea, despite having completed the transition to digital broadcast (ATSC) in 2012, still maintains analog broadcast near its borders for North Koreans watching South Korean TV in secret.
19. Freddie Mercury bequeathed the vast majority of his fortune to his ex-girlfriend (Mary Austin), and also entrusted her to ensure that the burial place of his ashes would remain secret.
20. The Rothschilds had such an efficient system of couriers that they knew Napoleon had lost at Waterloo a day before the government did. Nathan Rothschild kept it secret and immediately bought up the government bond market. He then sold the bonds for an enormous 40% profit two years later.
Before his death, Ed Sullivan believed he was suffering complications from his long-standing battle with ulcers. He did not know that he had been diagnosed with advanced esophageal cancer the month before, a diagnosis his family and doctors had kept secret from him.
22. The Powerpuff Girls were originally called the "Whoopass Girls" by their creator who did the pilot as a college project. The "secret ingredient" in their creation was accidentally spilling a can of Whoopass into the pot.
23. Beneath the streets of Los Angeles is a complex network of pedestrian tunnels that stretch several blocks. They've been used for secret transportation of mobsters, murderers and more than a billion dollars in cash; designated as fallout shelters and homeless shelters and used as backdrops for movies.
24. In 2000, Over 1000 priceless books disappeared from a mountaintop abbey in France to the confusion of the monks and the local police, despite reinforcing the library's doors and changing its locks. Turned out the culprit was using a long-forgotten secret passageway found in the public archives.
25. An employee of the Kodak Camera Company discovered in the 40s that there must have been some sort of nuclear test (Trinity test) on United States mainland. Realizing the importance of his discovery, he kept his findings a secret until 1949.