In June 1992, a joint archaeological team from CPAM of Tibet and Sichuan United University discovered several Buddhist grottoes on the Ali plateau. Of them, the relatively large ones located at Tonca and Pica villages within the territory of Jada county can be named "Tonca-Pica Grotto site" due to the close distance between the two villages. From May to August 1994,a team was sent to the grottoes again for their clearning and coding. There are about one hundred and sixty caves at Tonca and nearly one thousand at Pica, including the shrine, closet for meditation, store, and kitchen. The well-preserved colorful mural paintings in those shrines show Buddha, Buddhisattva, goddess, asparas, donators, etc. The grottoes whose date is believed to be somewhere between the 11th and 15th centuries shed much light on the Buddhist history and grotto art in the area.
