unexplained-events:

Skeleton Lake

Roopkund Lake, in the Indian Himalayas, is frozen for much of the year. But in warmer months it delivers a macabre performance, earning the nickname Skeleton Lake. After the lake melts, hundreds of skeletons (some with flesh still attached) begin to emerge. 

At first it was thought that all these people died simultaneously in a catastrophic event, but recent studies on the remains upended that theory. Studies showed that there wasn’t just one mass dumping of the dead, but several, spread over a millennium.

Further genetic analysis by researchers (particularly researchers Niraj Rai and David Reich) showed that the remains were mostly South Asian, East Asian, and Eastern Mediterranean and that a lot of the remains appeared hundreds and even a thousand years apart. Chemical signatures from the skeletons indicate that the individuals had significantly different diets, adding support to the notion that several distinct population groups are represented. Their sample size (they studied 38 different remains) also showed that none of the people were related.

None of the research has answered how and why all these remains got here. There’s no evidence of bacterial infections, so an epidemic was probably not to blame. Perhaps the challenging high-altitude environment proved fatal. Currently Skeleton Lake’s mystery remains unexplained.

SOURCE (def recommend reading the full story)