Fengxian, or Feng Xian Si (奉先寺), or Li Zhi cave is the Ancestor Worshipping Cave, which is the largest of all caves carved on the west hill built between 672 and 676 for Empress Wu Zetian. The carvings are claimed to be the ultimate in architectural perfection of the Tang dynasty. The shrine inside the cave measures 39 m x35m. It has the largest Buddha statue at the Longmen Grottoes. Of the nine huge carved statues, the highly impressive image of Vairocana Buddha is sculpted on the back wall of the Fengxian. The image is 17.14m high and has 2 m long ears. An inscription at the base of this figure gives 676 as the year of carving. The Bodhisattva on the left of the main image of Buddha is decorated with a crown and pearls. Also shown is a divine person trampling an evil spirit. The main Vairocana image’s features are plumpish and of peaceful and natural expression. Each of the other large statues are carved with expressions matching their representative roles. These were carved at the orders of Empress Wu Zetian, and are considered uniquely representative of the Tang dynasty’s “vigorous, elegant and realistic style.” The huge Vairocana statue is considered as “the quintessence of Buddhist sculpture in China.”

– Wikipedia

Guyangdong, or Guyang Cave, or Old Sun Cave, is recorded as the oldest Longmen cave with carvings in the Northern Wei style. It is also the largest cave, located in the central part of the west hill. It was carved under the orders of Emperor Xiaowen. The earliest carving in this limestone cave has been now dated at 478 AD, during the period when Emperor Xiaowen is thought to have been moving his capital from Datong to Luoyang. The Buddhist statues in the niches of this cave are very well sculpted. Also found here are 600 inscriptions in fine calligraphy of writings in the Northern Wei style. Many of the sculptures inside the cave were contributed by royalty; religious groups supported this activity. The cave has three very large images – the central image is of Sakyamuni Buddha with Bodhisattvas on either side. The features of the images are indicative of the Northern Wei style, typically of slim and emaciated figures. There are about 800 inscriptions on the walls and in the niches inside the cave, the most in any cave in China. There are two rows of niches on the northern and southern walls of the cave, which house a very large number of images; the artists have recorded their names, the dates, and the reasons for carving them.

– Wikipedia

Binyang has three caves, North Binyang Cave, Middle Binyang Cave and South Binyang Cave, of which the Middle Binyang Cave is the most prominent.
Binyangzhongdong (Chinese: 宾阳中洞) or the Middle Binyang Cave, is carved in the Datang style on the west hill, on the northern floor. It was built by Emperor Xuanwun to commemorate his father Xiaowen, and also his mother. It is said that 800,000 workers created it over the period from 500 to 523. In the main wall of this cave, five very large Buddhist statues are carved all in Northern Wei style The central statue is of Sakyamuni Buddha with four images of Bodhisattvas flanking it. Two side walls also have Buddha images flanked by Bodhisattva. The Buddhas, arranged in three groups in the cave, are representative of Buddhas of the past, the present, and the future. The canopy in the roof is designed as a lotus flower. There were two large bas-reliefs of imperial processions, that included Emperor Xiaowen, Empress Dowager Wenzhao, and the emperor’s late parents in worship. The reliefs were stolen completely in the mid-1930s. The emperor’s procession is now in the Metropolitan Museum of Art in New York and two thirds of the empress’s is in the Nelson-Atkins Museum of Art in Kansas City. While a few statues are sculpted with “long features, thin faces, fishtail robes and traces of Greek influence”, others are in Tang period natural style and heavily built.

– Wikipedia