Located in a stretch of the North Sea renowned for its strong currents and unpredictable climate, the Helgoland archipelago was under Danish control for a long time, before it fell into the hands of the British in 1814. It was finally won by the Germans in exchange for Zanzibar. Each year thousands of tourists are drawn here by the prospect of a cruise on the high seas and to see the island's red sandstone cliffs, 70km from the mouth of the Elbe.