The flute has been dated to prehistoric times. It has appeared in different forms and locations around the world. A three-holed flute made from a  mammoth  tusk (from the  Geißenklösterle  cave in the German  Swabian Alb  and dated to 30,000 to 37,000 years ago [1] ) was discovered in 2004, and two flutes made from  swans ' bones excavated a decade earlier (from the same cave in Germany, dated to circa 36,000 years ago) are among the oldest known musical instruments. A fragment of the  femur  of a juvenile  cave bear , with two to four holes, found at  Divje Babe  in  Slovenia  and dated to about 43,100 years ago, may also be an early flute. [2] [3]