Mainau Island lies just off the shores of Lake Constance in the far south-west of Germany, close to Switzerland and Austria. Feature include an Arboretum, over 150 years old, with giant sequoia trees. Around a million tulips, rhododendrons, scented roses, perennials and colourful dahlias bloom in the park and gardens. Palms and citrus plants lend a Mediterranean flair to the island in summer. The Teutonic castle completed in 1746 and the castle church are architectural highlights. (paraphrased from www.mainau.de)