The Northern Grotto and the Southern Grotto in east Gansu Province were excavated in the early 6th century and the main images there are the seven Buddhas. There are no sculptures of the Sukyamuni and Dobo sitting together, which is common in the grottos dug in the Northern Dynasty Period, thus the creation of the icons in the two places may have nothing to do with the Fahua Zen school. The internal spatial structure and the size of the icons indicate that they were probably used for confession purposes.
