The popemobile with Pope Benedict XVI drives along the main shopping street of Freiburg, September 24, 2011, with the Martinstor city gate pictured in background. Pope Benedict has praised Catholics in eastern Germany who held on to their Christian beliefs despite the "acid rain" that corroded their faith under the Nazis and communism.The Bavarian-born pontiff is on a four-day visit to Germany, his third visit to his homeland since he took over as head of the Catholic church. REUTERS/Michael Probst/Pool (GERMANY - Tags: POLITICS RELIGION)