The brass padlock, which came from a centuries-old shipwreck, had been puzzling researchers for years.
The world's largest single-dish radio telescope has detected a signal that astronomers have been unable to explain.
A mysterious caped crusader has been spotted around the British capital doing various good deeds for random strangers.
A cryptozoological creature, thought by some to be a giant exotic cat, has been reported to the police in Coventry, England.
The letter, which was written in code, had remained a complete mystery as the accompanying key had been lost.
The orbital platform - which was known as USA 32 - broke into pieces last month and nobody seems to know why.
The 17th recorded sighting has cemented 2026 as a bumper year for encounters with the Loch Ness Monster.
Several decades on, the case of Barney and Betty Hill still continues to spark debate and intrigue.
Several locals called the cops after witnessing a hairy hominid walking around the community of Damariscotta.
Authorities on Long Island are investigating what these individuals have been doing in the sewer system.
Back in 1992, two climbers who set out to tackle the Swiss Alps never returned, leading to a decades-spanning mystery.
A peculiar object resembling a small tripod is present in one photograph of a particular location, but then not in another.
The latest selection of files includes a cache of 12 previously unseen videos of mystery objects sighted around the world.
The pilots of a Mokulele Airlines flight recently had to take evasive action after an unidentified object 'popped' out of a cloud.
The long-standing mystery had concerned strange symbols found on the walls of old buildings across England.
Authorities attended the scene after a weird red substance was spotted leaking from a large semi-truck.
A vigilante has been taking matters into his own hands by catching and taping up thieves for local police officers to find.
The owner of the land on which the speakers were discovered has come forward to offer an explanation.
China has deployed an unidentified payload in orbit around the Earth using its secretive Shenlong space plane.
The case has remained a mystery for decades, prompting lawmakers to demand the release of all related documents.