Neuschwanstein is one of the most photographed castles in the world, and is often referred to as "the fairy-tale castle". Apparently, Walt Disney modelled his Disneyland Castle on it. Here's Wikipedia's description:
Neuschwanstein Castle (German: Schloß/Schloss Neuschwanstein, lit. New Swan Stone palace; IPA pronunciation: /nɔɪˈʃvaːnʃtaɪ̯n/) is a 19th century Bavarian palace. Located in Germany, near Hohenschwangau and Füssen in southwest Bavaria, the castle was built by Ludwig II of Bavaria as a retreat and as an homage to Richard Wagner, the King's inspiring muse. Although photography of the interior is not permitted,[1] it is the most photographed building in Germany[2] and is one of Germany's most popular tourist destinations.
The conception of the castle was outlined by Ludwig II in a letter to Richard Wagner, dated May 13, 1868;
"It is my intention to rebuild the old castle ruin at Hohenschwangau near the Pollat Gorge in the authentic style of the old German knights' castles...the location is the most beautiful one could find, holy and unapproachable, a worthy temple for the divine friend who has brought salvation and true blessing to the world."
The foundation stone of the building was laid September 5, 1869. Neuschwanstein was designed by Christian Jank, a theatrical set designer, rather than an architect, which says much regarding Ludwig's intentions and explains much of the fantastical nature of the resulting building. The architectural expertise, vital to such a perilously-sited building, was provided first by the Munich court architect, Eduard Riedel, and latterly by Georg Dollman and Leo von Klenze.
The castle was originally called "New Hohenschwangau Castle" until the king's death, when it was re-named Neuschwanstein, the castle of the Swan Knight, Lohengrin, of Wagner's opera of the same name. In origin, the castle has been the Schwanstein, the seat of the knights of Schwangau, whose emblem had been the swan.