The unicorn, according to Wikipedia:
"is a legendary animal from European folklore that resembles a white horse with a large, pointed, spiraling horn projecting from its forehead, and sometimes a goat's beard and cloven hooves. First mentioned by the ancient Greeks, it became the most important imaginary animal of the Middle Ages and Renaissance when it was commonly described as an extremely wild woodland creature, a symbol of purity and grace, which could only be captured by a virgin. In the encyclopedias its horn was said to have the power to render poisoned water potable and to heal sickness. Until the 19th century, belief in unicorns was widespread among historians, alchemists, writers, poets, naturalists, physicians, and theologians."
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"One traditional method of hunting unicorns involved entrapment by a virgin.
In one of his notebooks Leonardo da Vinci wrote:"
'The unicorn, through its intemperance and not knowing how to control itself, for the love it bears to fair maidens forgets its ferocity and wildness; and laying aside all fear it will go up to a seated damsel and go to sleep in her lap, and thus the hunters take it.'
"The famous late Gothic series of seven tapestry hangings The Hunt of the Unicorn are a high point in European tapestry manufacture, combining both secular and religious themes. The tapestries now hang in the Cloisters division of the Metropolitan Museum of Art in New York City. In the series, richly dressed noblemen, accompanied by huntsmen and hounds, pursue a unicorn against mille-fleur backgrounds or settings of buildings and gardens. They bring the animal to bay with the help of a maiden who traps it with her charms, appear to kill it, and bring it back to a castle; in the last and most famous panel, "The Unicorn in Captivity," the unicorn is shown alive again and happy, chained to a pomegranate tree surrounded by a fence, in a field of flowers. Scholars conjecture that the red stains on its flanks are not blood but rather the juice from pomegranates, which were a symbol of fertility. However, the true meaning of the mysterious resurrected Unicorn in the last panel is unclear. The series was woven about 1500 in the Low Countries, probably Brussels or Liège, for an unknown patron. A set of six engravings on the same theme, treated rather differently, were engraved by the French artist Jean Duvet in the 1540s.
Another famous set of six tapestries of Dame à la licorne ("Lady with the unicorn") in the Musée de Cluny, Paris, were also woven in the Southern Netherlands before 1500, and show the five senses (the gateways to temptation) and finally Love ("A mon seul desir" the legend reads), with unicorns featured in each piece.
Facsimiles of the unicorn tapestries are currently being woven for permanent display in Stirling Castle, Scotland, to take the place of a set recorded in the castle in a 16th century inventory.
Shakespeare scholars describe unicorns being captured by a hunter standing in front of a tree, the unicorn goaded into charging; the hunter would step aside the last moment and the unicorn would embed its horn deeply into the tree."
See: http://en.wikipedia.org/wiki/Unicorn