"The Camargue is an ancient breed of horses found in the Camargue area in southern France. For centuries, possibly thousands of years, these small horses have lived wild in the harsh environment of the Camargue marshes, wetlands of the Rhone delta. They developed the stamina, hardiness and agility for which they are known today. They are the traditional mount of the gardians–the Camargue "cowboys" who herd the black Camargue bulls used in bullfighting in southern France. Camargue horses galloping through water are a popular and romantic image of the region.... 
Camargue horses are always gray. This means that they have black skin underlying a white hair coat as adult horses. They are born with a hair coat that is black or dark brown in colour, but as they grow to adulthood, their hair coat becomes ever more intermingled with white hairs until it is completely white.
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Some researchers believe the Camargue are descended from the ancient Solutré horse hunted during the Upper Paleolithic period. Extensive archeological evidence has been found in the present-day Burgundy region of France.[1][2] The Camargue breed was appreciated by the Celtic and Roman invaders who entered the Iberian Peninsula.
Their calm temperament, agility, intelligence and stamina has resulted in these horses being used for equestrian games, dressage, and long distance riding, which is growing in popularity in France."
(From Wikipedia )
