Reassembling a 15th century ship: "The world's largest 3-D puzzle"

The remains of a British ship that set sail years before Columbus were discovered two decades ago in a south Wales riverbank. After 20 years of painstaking restoration, archaeologists have started to reassemble the 15th century wreck. With almost 2,500 pieces, it has been called the world's largest 3-D puzzle. The BBC's Tomos Morgan has the story on the Newport Ship Conservation Project.