Hot air balloons fly off in the Shuping scenic area of Danxia landform, a unique type of landscapes formed from red sandstone and characterized by steep cliffs, in Xinghua Village of Shuping Town in Yongdeng County under Lanzhou, capital of northwest China's Gansu Province, Oct. 15, 2016. A hot air balloon tourism base opened to the public on Saturday. Visitors could overlook Danxia landform from the sky by taking hot air balloons. (Xinhua/Fan Peishen)