Mogao Grottoes has the longest history.
Mogao Grottoes, commonly known as Thousand Buddhas Cave, is located in Dunhuang at the west end of the Hexi Corridor. It was built in the pre-Qin period of the Sixteen Kingdoms, and has gone through the construction of the Sixteen Kingdoms, Northern Dynasties, Sui, Tang, Five Dynasties, Xixia, Yuan and other dynasties. It has formed a huge scale, with 735 caves, 45,000 square meters of murals, and mud paintings. With 2,415 colorful sculptures, it is the largest and richest Buddhist art site in the world.
The Yungang Grottoes are located at the southern foot of Wuzhou Mountain, 17 kilometers away from the western suburbs of Datong City, Shanxi Province, northern China. The grottoes are carved into the mountain and stretch for 1 kilometer from east to west. There are 45 main caves, 252 large and small cave niches, and more than 51,000 stone statues. It is one of the largest ancient grottoes in China. Together with Dunhuang Mogao Grottoes, Luoyang Longmen Grottoes and Tianshui Maijishan Grottoes, it is also known as the Four Four Grottoes in China. A treasure trove of great grotto art. In the Northern Wei Dynasty, the excavation of the Yungang Grottoes started from the beginning of Emperor Wencheng's reign (460) and continued until the fifth year of Emperor Xiaoming's Zhengguang (524), a period of more than 60 years. After that, in the Eastern Wei, Northern Qi, Sui and early Tang Dynasties, Pingcheng was changed to Heng'an Town, Yunzhong County.
The Longmen Grottoes were excavated during the reign of Emperor Xiaowen of the Northern Wei Dynasty. Afterwards, they were built on a large scale for more than 400 years through the Eastern Wei, Western Wei, Northern Qi, Sui, Tang, Five Dynasties, Song and other dynasties. They are 1 kilometer long from north to south. Today, There are 2,345 cave niches, more than 100,000 statues, and more than 2,800 inscriptions. Among them, "Twenty Products of Longmen" is the essence of Wei calligraphy stele, and "Stele of Yique Buddhist Niche" written by Chu Suiliang is a model of regular script art in the early Tang Dynasty.