In the days of sail Viking longships and Hanse roundships plied the waters of the Baltic, and for centuries the area formed the axis of a five-nation power struggle, as bids were made for glory both on land and at sea. Today towering ferries and container ships criss-cross routes between cities with a proud past, and travellers are entranced by legendary castles and captivating palaces. This is the fascinating story of the northern inland sea and of the peoples of its shores, from the ice age to the nuclear age.