Saint-Jean-de-Luz (săN-zhäN-də-lüz) [key], town (1990 pop. 13,181), Pyrénées-Atlantiques dept., SW France, in the Basque Provinces (see Basques), on the Bay of Biscay. It is a beach resort with a casino and a sardine- and tuna-fishing port. Louis XIV married (1660) Marie Thérèse of Austria there. Saint-Jean-de-Luz has a 16th-century Basque church.