All About Unicorns
Information on unicorns in the Middle Ages, ancient and prehistory; also covering heraldry, legends and popular culture.
Lore of the alicorn, sightings, heraldry, myths, bible references, and international history.
Flickr: Unicorn - Licorne - Liocorno - Einhorn
Works of art in history, ranging from full pieces to individual detail.
Heraldic America: The Unicorn in Canada
International history, ancient history, heraldry, and lore, by Auguste Vachon.
An overview of the unicorn in history, with picture archive.
Wikipedia: Elasmotherium, Giant Unicorn
A now extinct type of rhinoceros, theorized as a possible origin.