The skull of a Viking-era man who had part of his skull cut out in the world’s oldest surgical procedure has been unearthed. The remains of a man between 17 and 24 revealed a large oval hole in his skull, measuring three cm in diameter, from around the 9th century AD. Archeologists believe he may have undergone trepanation—an ancient surgical procedure in which a hole is bored through a living human’s skull for migraines or seizures. The find was made during a University of Cambridge training