Pope Benedict XVI and German President Horst Koehler walk past guard at the Cologne-Bonn international airport. Pope Benedict XVI and German President Horst Koehler review the guard of honour at the Cologne-Bonn airport August 18, 2005. Pope Benedict arrived in his German homeland on Thursday on the first international trip of his pontificate, a visit to the World Youth Day attended by hundreds of thousands of young Catholics. REUTERS/Ina Fassbender