
Located in the Yi River’s west bank, Grottoes 521 (North Grotto) and 522 (South Grotto) are twin grottoes that were built in the Tang dynasty (618–907). Facing east, they share the same front chamber. Three warriors are carved in relief at the entrances to the rear chamber, two at Grotto 521 and one at Grotto 522. The muscular figures have bare upper bodies and fierce eyes. At their sides, the hands are clenched into tight fists. Thirty-four small niches above and around the warriors are carved into the surface of the wall.
Grotto 521’s rear chamber has a vaulted ceiling and measures 3.6 m in width, 3.5 m in height, and 6.9 m in depth. On the right side of the doorway there are a seven-tier pagoda and two niches containing Buddha triads. On the left of the doorway are one large and eight small arched niches. The ceiling is decorated with a lotus surrounded by eight apsaras.
The main Buddha statue on the back (west) wall is 2.25 m in height. The nimbus is engraved with a lotus petal pattern and seven small Buddhas. Seated in full lotus position on an octagonal lotus throne, the main Buddha has a swirl-patterned usnisa and wears a double-collared monastic robe. The vitarka (teaching) mudra is formed with the left hand, while the right hand is raised. There are two lions, both damaged, engraved below the throne. Disciples, wearing similar monastic robes, stand on either side of the Buddha. The disciple on the right holds an incense burner in both hands while the one on the left has palms joined.
A Buddha, two Bodhisattvas, and one Heavenly King are depicted on the north wall. The Buddha and Bodhisattvas have petal-shaped nimbuses engraved with lotus petal patterns, and stand on lotus pedestals. The Buddha has a swirl-patterned usnisa and wears a monastic robe that covers both shoulders. The robe descends in smooth, U-shape folds. The Bodhisattvas on both sides wear ornaments, stoles, and long garments. The Bodhisattva on the left grasps the stole with the left hand while the right is held near the chest. The hands of the Bodhisattva on the right are damaged, as are the heads of both Bodhisattvas. The Heavenly King is also damaged. Eight small arched niches are found behind the king. The statues on the south wall are similar to those on the north wall. The south wall Heavenly King has wavy hair, a crown, and armor. This less damaged king stands atop a demon, and behind him are 11 small niches.
Grotto 522 has a rectangular layout, with an arched ceiling in front and a vaulted ceiling at the back. The grotto is 3.1 m in height and 7.3 m in depth, with a 1.87 m frontal width and a 2.47 m rear width. Within the grotto, there are nine rows of seated Buddhas to the right of the entrance, below which two niches house Buddha triads. The left side of the entrance is badly damaged. Only the remnants of an Avalokitesvara Bodhisattva image and Thousand Buddha motif in the upper section remain. The main statue, Maitreya Buddha, is seated along the back wall upon a high throne. The Buddha measures 2.1 m in height and has a petal-shaped nimbus. Damage is apparent above the chest and on the right arm; while the left hand rests on the knee. The Buddha was flanked by two disciples and two Bodhisattvas, though the left Bodhisattva is now missing. All the figures have nimbuses. The disciple on the right joins palms before the chest, while the one to the left carries an incense burner in both hands. The Bodhisattva on the right has long stoles draped across the body, and the abdomen is adorned with two strings of long ornaments threaded through a jade disc. The head and hand of the Bodhisattva are damaged. Next to the now missing Bodhisattva are three arched niches. The north, south, and front (east) walls are covered with the Thousand Buddhas, all of whom are seated in full lotus positions on lotus thrones.
For more details, go to the Encyclopedia of Buddhist Arts: Caves R-L, page 676.