Greece's marble Olympics stadium gets a deep clean

Athens' iconic Panathenaic Stadium is undergoing its first systematic cleaning in more than a century. The U-shaped stadium, built entirely from white marble and rebuilt for the first modern Olympics in 1896, is being carefully cleaned with low-pressure water and a little steam. Conservators say they are carefully removing accumulated dirt, organic material, weeds and decades-old chewing gum without damaging the historic stone. (AP Video by Srdjan Nedeljkovic and Derek Gatopoulos. Drone video by Thanassis Stavrakis. Production by Theodora Tongas.)