The Caldera
By John FlanaganThe Caldera is the seventh book in the Brotherband Chronicles series by John Flanagan. Set in a world of Viking-like cultures, the story follows Hal and his crew, the Herons, as they embark on a perilous mission to find the fabled land of Santorillos. Their journey takes them to the treacherous Caldera, a volcanic island inhabited by ruthless pirates and deadly natural forces.