Vividly bright stalactites hang from the ceiling of a karst cave in Dongyanglou village, Tai'an city, in East China's Shandong province. Crustal deformation that took place billions of years ago resulted in a great rift valley between Mount Taishan and Culai Mountain, an underground valley that later turned into the biggest karst cave in the world. It houses a great variety of stalactites and each is a unique formation. The cave was discovered accidentally in 2003 and is now open to visitors, who can appreciate the cluster of geological wonders. The scenic spot is a 4A-level tourist site and attracts over 2 million visitors annually from home and abroad.[Photo by Ju Chuanjiang/China Daily]