Centaur Aisle is a fantasy novel by American writer Piers Anthony, the fourth book of the Xanth series.King Trent has left Xanth on a mission of trade to Mundania and has left Dor as temporary king. When Trent fails to return after some time, Dor must find a way to rescue Trent. He is informed that the means to rescue Trent lies to the south on Centaur Isle, the home of a tribe of centaurs. Source: Wikipedia (en)