Support WBURChina's Great Wall Is Crumbling In Many Places; Can It Be Saved?Play04:30Download AudioAnthony KuhnJanuary 27, 2016 ShareQiao Guohua patrols a 5-mile stretch of the Great Wall of China. Roughly a third of the wall's 12,000 miles have crumbled to dust, and saving what's left may be the world's greatest challenge in cultural preservation. (NPR)