If you're a fan of king Arthur, or a student of the many grail romances that have filled the ages, then a visit to Valencia's beautiful Gothic Cathedral dedicated to Santa Maria is a must, held in the holiest part of the church, the Sala Capitular, a sacred chalice that the locals claim is the genuine "holy grail" as used by Jesus at the last supper.
Needless to say, the authenticity of the relic is hotly disputed, but for the faithful, its presence is proof enough. A parade of pilgrims pass the cup all day every day, crossing themselves as they do, and perhaps this may be enough.