Vietnam’s Cham Islands, renowned for tropical beaches, granite cliffs and the swallows now circling dizzily overhead have a ominous history. The names for these islands reflect their shape and character – one is called “East Wind”, another “Tomb”. That is the first clue to the history of these waters. This is the story of the coast that sank 1,000 ships. The secrets of one of the world’s busiest ancient shipping routes are waiting to be discovered – but could treasure hunters get there first?