Used book – The Iceberg, Emily Rodda

Rowan, the young keeper of the Boukchahs, is anything but a hero. Small, sensitive, and fearful, he is nevertheless the one the witch has chosen to lead the expedition. Composed of eight brave villagers, it will have to face the ice mountain and its traps. Their goal: to reach the summit, the kingdom of a terrible dragon, and free the spring that will restore life to the village and its herd of Boukchahs. But who will be the bravest and most cunning of all?