Using LiDAR technology, archaeologists found that prehistoric monuments across County Wicklow may have served as routes to guide spirits to the afterlife.

Starting at least 7,000 years ago, prehistoric humans in the Arabian Desert used the Umm Jirsan cave as shelter from the blistering heat of the arid landscape above.

Now recognized as the deepest blue hole on Earth at a depth of 1,378 feet, the Taam Ja' ocean sinkhole located in Mexico's Chetumal Bay has surpassed the competition by hundreds of feet — and experts still don't know how deep it goes.

Better known as "Bugsy," celebrity gangster Benjamin Siegel ran criminal rackets in New York and Los Angeles before creating Las Vegas as we know it.

In 360 B.C.E., Plato wrote that Atlantis was once a powerful civilization — but the gods sent earthquakes to destroy the island nation when its people became greedy and proud.

Buried beneath the sprawling Wolf's Lair complex were the skeletons of three adults, a teenager, and a baby — but the details of their macabre deaths are still unclear.

Go inside the chilling story of Peter Madsen, the entrepreneur-turned-murderer who killed Kim Wall aboard his submarine on August 10, 2017.

Once known as the "City of Smoke," Pittsburgh used to produce over half of America's steel. Though the steel industry largely crumbled by the 1980s, the city made an impressive comeback by reinventing itself.

Measuring nearly 14 inches long, the footprints of Fujianipus yingliangi are the largest of their kind — and likely belonged to one of the biggest raptors to ever walk the Earth.

Beginning in 1979, former librarian Marion Stokes privately recorded broadcasts from multiple televisions at once, 24 hours a day, eventually accumulating a startling 71,000 tapes of television history.

First discovered in 1994, the origins of the mysterious "Excalibur" sword found in Valencia, Spain had eluded researchers for 30 years.