These Mysteries Still Need Some Explaining

Back in 1836, three boys chasing rabbits around Arthur's Seat, the hill famously overlooking Edinburgh, stumbled into a cave and found 17 miniature coffins containing little dolls. There are a couple theories about their purpose — an honorific burial, or possibly a stash of charms to be sold to superstitious sailors — but nobody knows for sure.

Stretching for a mile along the Pisco Valley in Peru, nobody really knows why this ribbon of 6,000 holes, each three feet across and 20 to 40 inches deep, even exists. Some suspect it's a part of an Incan tax system, but the holes could very well predate the Incas. They're visible on Google Earth, and that's pretty cool.

Apparently some archaeologists filming a documentary in China opened up a sealed, 400-year-old tomb and found a ring shaped like a little Swiss watch, with the word "Swiss" engraved on the back and showing a time of 10:06. No one has been able to figure out if it's a forgery or not.

Experts believe that this one-of-a-kind bike was built in 1916, but it wasn't discovered until 1967, when a plumber found it bricked up behind a wall in Chicago. Nobody knows for sure who the Traub was who built it, but all the experts agree he was ahead of his time. Why he didn't go on to make more and rock the motorcycle industry to its core remains a mystery.