Heligoland, or Helgoland in its native German, is a small archipelago in the North Sea, situated off of the northwest coast of Germany. The larger of its two main islands is the eponymous Heligoland, with the smaller island of the pair being called Düne. The latter of these is home to the archipelago's airport, Flughafen Helgoland-Düne (HGL). In 1974, a Boeing 737 almost touched down there.