Once, a million people flocked to Nuremberg for the Nazi Party Rallies. A new exhibition makes the significance of the site tangible. It has been running in a trial phase since May, and now the Nuremberg Documentation Center is officially opening its new exhibition on the former Nazi Party Rally Grounds. Among those expected at the opening ceremony on Wednesday morning (11:00 a.m.) are former German President Christian Wulff and Nuremberg's Mayo…