It is the kind of traverse that cavers approach with careful preparation, appropriate equipment, and awareness that the cave does not accommodate mistakes easily.

For an ancient person, making the same traverse with a torch that had to be carried and maintained, with no modern protective clothing, with no safety team and no detailed knowledge of the cave’s layout, the difficulty would have been substantially greater.

And yet the evidence — both the bones themselves and the traces that researchers found on cave surfaces — suggests that someone made that traverse, approximately eight thousand eight hundred years ago, and did not come back out.

Going Deep Before Electricity Existed