A sign reading "stop" in German and Polish is seen in the former Nazi German death camp of Auschwitz in Oswiecim, Poland, Friday, July 29, 2016. Pope Francis paid a somber visit to the Nazi German death camp of Auschwitz-Birkenau Friday, becoming the third consecutive pontiff to make the pilgrimage to the place where Adolf Hitler's forces killed more than 1 million people, most of them Jews. (AP Photo/Gregorio Borgia)