Which dynasty was the Xumishan Grottoes excavated?

Xumishan Grottoes are located in Yuanzhou District, Guyuan City, Ningxia. It is located on the mountain peak at the northern foot of Sikouzi River, a tributary of Liupanshan Mountain, 55 kilometers north of the city. Xumishan Mountain belongs to Liupanshan Mountain, and its basement is composed of purple sandstone, sandstone and shale. It is 2003 meters above sea level, with rugged peaks, flowing water and beautiful scenery. It is one of the famous scenic spots in Ningxia. Xumishan Grottoes are famous Buddhist grottoes on the Silk Road. It is one of the top ten famous grottoes in China. It was built in the Northern Wei Dynasty, and continued to be built and repaired in the Western Wei, Northern Zhou, Sui, Tang, Song and Ming Dynasties. For a long time, it has been the largest Buddhist temple site on the westward road of Chang 'an, and it is known as "Dunhuang in Ningxia". Xumishan Grottoes is a national key cultural relic protection unit. It was originally called Fengyi Mountain. In the Tang Dynasty, Xumishan began to be called "Jingyun Temple", which was followed in the Five Dynasties, Song Dynasty, Xixia, Jin Dynasty, Yuan Dynasty and early Ming Dynasty. As a synonym of Buddhist appellation and grottoes, Xumishan should be pushed to the Song Dynasty. Xumishan Grottoes was founded in the reign of Emperor Xiaowen of the Northern Wei Dynasty (477 ~ 499) and flourished in the Northern Zhou and Tang Dynasties. It is one of the first ten grottoes excavated in China and one of the famous Buddhist grottoes on the ancient Silk Road. Its excavation scale, sculpture style and artistic achievements are comparable to those of Yungang in Datong and Longmen in Luoyang. After renovation and management in the Western Wei Dynasty, the Northern Zhou Dynasty, the Sui and Tang Dynasties, the Song Dynasty, the Yuan Dynasty, the Ming Dynasty and the Qing Dynasty, it became the largest Buddhist temple between Chang 'an and Guanwai in ancient China, lasting for more than 1500 years. "Xumishan" was originally transliterated in Sanskrit, and it is said that it is a famous mountain in ancient Indian mythology, and it is also called "Datura" in Buddhist scriptures. It can also be called Sumi House, Sumi House, Sumi House, etc. In Indian legends, it means "Miaogao", "Anming" and "Shanji". There are more than 200 Wan Li in the legendary Mount Sumi, which is three times the height from the earth to the moon. In other words, we live on 200 earths. Xu Mi is of great significance in Buddhism. Also called Xu Mi House, it is a famous mountain in ancient Indian myths and legends. According to Buddhism, it is the king in the mountain and the center of the world. In China, it not only exists in Ningxia, but also is one of the most famous Lamaism and Yellow Sect temples in Beijing. According to Buddhist teachings, the Hanazono Sakura world is divided into three parts: upper, middle and lower parts, namely wind wheel, water wheel and golden wheel, and Xumi Mountain here is the golden wheel. The golden wheel is on the ground, and there are 938 seas on the ground, which is where human beings live. Further up, there is a palace in the east, west, north and south, representing four continents: Dongsheng Shenzhou, Nanzhan Buzhou, Xiniuhe Prefecture and Beiju Luzhou. Further up, it is a vast universe full of astronomical constellations. At the top of the stars (the sky is at the top of Mount Sumi), there is a unique small altar city, which is the holy land where Shi Di lives, the so-called Xanadu. The Buddhist sutra "Time Wheel Sutra" says that the earth consists of five substances: wind, fire, water, earth and air, and there are seven golden mountains and Xumi Mountain. At the bottom of the world is a wind wheel, above it is a water wheel, and above it is a golden wheel, that is, a ground wheel. In the creationism of Bonism in ancient Tibet, a king named Danquge in South Kadong had five original substances: earth, water, fire, wind and air. The mage collects them, puts them into the body, breathes gently and blows the wind. When the wind rotates in the form of a light wheel, there is fire, and the fire is getting bigger and bigger. The hot air and cool wind of the fire produced dew (water), which was exposed on it. This is the origin of Mount Sumi. Cave temple, referred to as grottoes for short, is a Buddhist temple building built on a cliff. It originated in India. It is a place where Sakyamuni, the founder of Buddhism, and his disciples meditate. It is often called "stone room". After the Eastern Han Dynasty, Buddhism was introduced into Chinese mainland from the Western Regions. From the Northern Wei Dynasty to the Sui and Tang Dynasties, a large number of new caves were excavated everywhere. It gradually declined after the Tang Dynasty. Architectural styles are divided into central columns and non-central columns. Grottoes were dug by Buddhism on cliffs or stone walls along the river. The start and development of Xumishan Grottoes are similar to other grottoes in northern China. Since ancient times, the location of Xumishan Grottoes has been the transportation hub and strategic location of the Central Plains leading to Hexi Corridor and the north and south of the desert. After the opening of the Silk Road, it became the only place for the eastern section of the Silk Road and the shortest place from Chang 'an to the Western Regions. In the Tang Dynasty, in order to strengthen the border defense, the Tang Dynasty set up the "Shimenguan Gate" here, which directly restricted the military and traffic between the Central Plains and the western regions, making it known as the "Guanzhong Throat". In the Song Dynasty, it was also a dangerous pass in Xiaping City (Huangduobao), where Huaide Army was stationed. Located in the north of the desert, Xumi Mountain is the main road to the west. It is the first famous Buddhist grotto shrine after the Silk Road left Chang 'an in the west, and it is also a famous ancient Shimenguan site. In the Qing Dynasty, Gansu Tongzhi said: "Nine miles north of the state, there is an ancient temple on the mountain of Xu Mi, which is full of pine and cypress, that is, the ancient Shimenguan site." Shimenguan, one of the famous seven passes around Sui and Tang Dynasties, is the gateway to the capital Chang 'an in the northwest, and also the gateway to shield the Central Plains and Chang 'an.