What is a miracle? In this episode of Decoding Christianity, host Christy Kenneally asks why, even today, people all over the world quest after miracles. He considers one of the earliest and most significant of miracles, Constantine's vision on the Milvian Bridge in the 4th century and investigates the connection between saints and miracles, joining pilgrims on their journeys to the sites of miraculous happenings from Ethiopia to Wales.