One June, a man climbed into the Ötzal Alps, on today’s Austrian–Italian border.

Dressed in leather and fur, he was mid-40s and extremely fit. He carried a wooden bow, flint-tipped arrows, and a copper axe.

He had no way of knowing that in an hour he’d be dead.

5,300 years later, some hikers discovered his body, melting out of a glacier.

Local police called in forensic experts, and so began a 30-year investigation into the best-preserved mummy from pre-modern history.

They traced the minerals in his teeth to a nearby groundwater source, to determine where he lived.

They looked at food and pollen in his gut to re-create his last day of meals and where he ate them.

Ötzi the Iceman, as they called him, had walked from his mountain home to the valley floor. That night, judging from a telltale slash on his hand, he got into a knife fight.

The wound had begun to heal by the time he died, suggesting he won it.

What had not healed were a fatal arrow wound to his back and a cracked skull. Someone had tracked him into the mountains and ambushed him.

His valuable copper axe was not taken, suggesting a revenge killing. Perhaps the killers buried him in snow, beginning his mummification.

Today, Ötzi rests in a museum freezer near where he was discovered. A model of him in life stands in the same building, while 3D printings of his body are studied around the world.