Originally Cave 4 was part of a group of three caves, together located directly above Cave 2. Cave 4 and Cave 6 form a pair, with Cave 5 in the middle. Historic photographs show that Caves 4 and 6 had Buddhas and bodhisattvas seated on lotus thrones accompanied by standing attendant figures on an altar around three walls. Today there are no long any sculpted figures. Because the sculpted figures were not attached to the thrones or walls of the cave they were relatively easily removed and have left no traces but for the thrones and pedestals. In the middle of the twentieth century, even these were cut away to make room for storage. Some of the fragments of fine sculptures remaining at this site can be identified as originating from Cave 4. The engraving of an excerpt from the Lotus Sutra still remains intact on the upper part of the cave. It is the chapter entitled the “Universal Gateway of Avalokiteśvara,” or Guanshiyin pumen pin (also known as the Guanyin sutra) describing the benefits of faith in Avalokiteśvara, the bodhisattva of mercy, who has powers to take many forms to save those in need of help.