Breitnau is a municipality in the district of Breisgau-Hochschwarzwald in the Black Forest in Baden-Württemberg in southern Germany.
Breitnau is first mentioned 1275 as Breittnowe but is probably older since the first church was built around 1200. The land was owned by The Family von Falkenstein but sold in 1408 to the Family Schnewlin von Landeck.
Marie Antoinette, Johann Wolfgang von Goethe and Felix Mendelssohn Bartholdy stayed at the Hotel Sternen in the valley of Höllental.
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