The conquistadors, as American schoolchildren have long been taught, sought vainly for El Dorado; here is the legend that inspired their dreams, based on the 1541 account of an Indian in Colombia. The wife and daughter of a wealthy Chibcha king are lured into the holy Lake Guatavita by an entrancing sea serpent. Desolate, the king pines and neglects his duties until the high priest assures him that his wife and daughter are well and happy under the lake; it is not yet time to join them, but an annual ceremony in which the king himself is gilded (hence ``El Dorado'') and fabulous jewels are given to the serpent will keep the kingdom safe. The author's handsome, lightly stylized art glows with jewel-like colors. Just right for giving added dimension to a unit on explorers. (Folklore/Picture book. 5-11)