A highlight of London's British Museum is one of its earliest acquisitions called the Parthenon Marbles, sculptures that once decorated the great 5th century B.C. temple on the Acropolis in Greece. They are considered to be among the great achievements of the classical world, but the Parthenon Marbles were acquired by the museum more than 200 years ago, when Greece was under control of the Ottoman Empire. And in an ongoing dispute with London, as some major cultural institutions reassess how they obtained colonial and classical relics, Greece has been working to bring the artifacts back. NewsHour Weekend Special Correspondent Christopher Livesay reports.