Druids: Voyage of Discovery (Druids #6)

With Rome's powerful allies on his heels, druid Gwynlan's search for the elusive reason for a series of brutal monastic murders takes him and his companions northwards to the land of the enigmatic Picts. It becomes apparent that the talismanic fate of the Treasures of the Britons is closely entwined with the Picts' own inheritance. Crossing frozen seas to a distant land across the ocean, Gwynlan searches for the truth while his deadly adversaries draw closer. But far from being a land of myth and legend, this new world is a haven for the Cauldron of Rebirth, revealing unexpected truths.