<P> The unicorn is a legendary creature that has been described since antiquity as a beast with a single large, pointed, spiraling horn projecting from its forehead . The unicorn was depicted in ancient seals of the Indus Valley Civilization and was mentioned by the ancient Greeks in accounts of natural history by various writers, including Ctesias, Strabo, Pliny the Younger, and Aelian . The Bible also describes an animal, the re'em, which some versions translate as unicorn . </P> <P> In European folklore, the unicorn is often depicted as a white horse - like or goat - like animal with a long horn and cloven hooves (sometimes a goat's beard). In the Middle Ages and Renaissance, it was commonly described as an extremely wild woodland creature, a symbol of purity and grace, which could be captured only by a virgin . In the encyclopedias, its horn was said to have the power to render poisoned water potable and to heal sickness . In medieval and Renaissance times, the tusk of the narwhal was sometimes sold as unicorn horn . </P> <P> Unicorns are not found in Greek mythology, but rather in the accounts of natural history, for Greek writers of natural history were convinced of the reality of unicorns, which they believed lived in India, a distant and fabulous realm for them . The earliest description is from Ctesias, who in his book Indika ("On India") described them as wild asses, fleet of foot, having a horn a cubit and a half (700 mm, 28 inches) in length, and colored white, red and black . Aristotle must be following Ctesias when he mentions two one - horned animals, the oryx (a kind of antelope) and the so - called "Indian ass". Strabo says that in the Caucasus there were one - horned horses with stag - like heads . Pliny the Elder mentions the oryx and an Indian ox (perhaps a rhinoceros) as one - horned beasts, as well as "a very fierce animal called the monoceros which has the head of the stag, the feet of the elephant, and the tail of the boar, while the rest of the body is like that of the horse; it makes a deep lowing noise, and has a single black horn, which projects from the middle of its forehead, two cubits (900 mm, 35 inches) in length ." In On the Nature of Animals (Περὶ Ζῴων Ἰδιότητος, De natura animalium), Aelian, quoting Ctesias, adds that India produces also a one - horned horse (iii. 41; iv. 52), and says (xvi. 20) that the monoceros (Greek: μονόκερως) was sometimes called cartazonos (Greek: καρτάζωνος), which may be a form of the Arabic karkadann, meaning "rhinoceros". </P> <P> Cosmas Indicopleustes, a merchant of Alexandria who lived in the 6th century, made a voyage to India and subsequently wrote works on cosmography . He gives a description of a unicorn based on four brass figures in the palace of the King of Ethiopia . He states, from report, that "it is impossible to take this ferocious beast alive; and that all its strength lies in its horn . When it finds itself pursued and in danger of capture, it throws itself from a precipice, and turns so aptly in falling, that it receives all the shock upon the horn, and so escapes safe and sound". </P>

Where did the legend of the unicorn come from
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