Michael Speaks, the leader of the Blue Nile expedition, waits for me outside a warehouse in Addis Ababa, Ethiopia’s capital city, where our gear is stored. A tattered T-shirt hangs from his muscular shoulders, and wire-rimmed glasses are perched on his angular face. A stoic man of few words, he lives alone in a cabin in the Alaskan mountains. For 20 years, he has been a guide on the world’s most demanding rivers. “Hey, see this,” says Speaks. He wades through a tangle of dusty equipment and hoists a crumpled aluminium tube. “Used to be a raft frame. Hippo bit my rig on the Omo [a river in southern Ethiopia] last year. Opened her mouth and just like that, sucked in an entire tube. One of her tusks got caught on the frame. She shook us about like a mouse.” He tosses the tube onto a pile of garbage in one corner. “Finally had to jam an oar into her mouth to get her off. “I got here only yesterday,” he adds, “and, as far as I can see, none of our permissions is in order. Tomorrow we meet the Ministry of Defence.” For several months, Ethiopia and Eritrea have been battling over a disputed triangle of land, blasting away at each other with rocket launchers, bombs and jets. Our route along the