Tenglong Cave, located in Enshi Tujia and Miao autonomous prefecture, Hubei Province, is a renowned karst wonder in China. With an explored length of 59.8 kilometers, it covers over 2 million square meters. Here, the Qingjiang River—Enshi's mother river—plunges into the earth like a dragon swallowing water, forming a 16.8-kilometer underground stream with a 165-meter drop. (Edited by Huang Jingjing and Liu Yunyun)