Although the water looks unappealing, Kristin Romey prepares herself to plunge into the depths. And right above her head, there’s a big clue as to why she’s putting herself through this ordeal. In this part of the north of Sudan, there’s a pyramid — a monument to a long-lost monarch that hints at a kingdom that once held sway over vast swathes of northern Africa. And when Romey and her colleague reach their destination, what they find is truly astonishing.