Danxia landform is seen at a geopark near Zhangye, northwest
China's Gansu Province, April 11, 2011. Danxia, which means
"rosy cloud," is a special landform formed from reddish
sandstone that has been eroded over time into a series of
mountains surrounded by curvaceous cliffs and many unusual
rock formations. (Xinhua/Gao Jianjun)