Tour buses run on the Guoliang cliff corridor in Guoliang Village, Huixian County, central China's Henan Province, May 13, 2017. The Guoliang cliff corridor is a 1,300-meter-long road built along the cliff of 1,000 meters high. The construction of this miraculous road lasted five years from 1972 to 1977, and was built purely by hand by villagers of Guoliang Village. (Xinhua/Li An)