I grew up in Girona, the Catalan city in Spain where Jews flourished until their tragic expulsion more than five centuries ago. Everywhere I walked, their shadows surrounded me. Hidden among the maze of alleyways east of the Onyar River is the former Jewish neighborhood, the Call, full of synagogues, yeshivas, and other Jewish monuments. Girona was home to one of the most important Kabbalistic schools in Europe...