The Elf Queen Of Shannara: The Heritage of Shannara, book 3 by Terry Brooks
Wren Ohmsford, Scion of Shannara, came from the Westlands, where she lived the life of a Rover. Now she, like her kinsmen, Par and Walker Boh, has been called upon to help the shade of Allanon fight the totalitarian power of the Federation. She must find the Elves, who disappeared from their strongholds more than one hundred years ago ...But even knowledge of the Elves is hard to find - only a blind, wise woman of the West knows something of their location. On her advice, Wren and her Rover companion, Garth, journey to the coast of the Blue Divide, where they build a fire and let it burn for three days. With the unexpected help that their blaze attracts, they reach the isle of Morrowindle and near their goal - to find the last of the Elves. But they also find dangers such as they could not have imagined, and Wren will make a discovery that will change her life for ever.