The pope addressed the crowd, many of whom were wearing leather, following mass. He said prayers for "every human life, especially the most fragile, defenceless and threatened."
"Just because we're motorcyclists doesn't mean we're not Catholics," Italian biker Emmanuele Jaconi told the Guardian.
"It's just a hobby. We like to drive our bikes around, and if the pope thinks it's good then all the better," a German biker said.
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