Kyaukgu Umin is situated about 2 miles to the east of Nyaung U town. It is one of the four monuments in Bagan built of stone brick. Kyaukgu Umin meaning the stone cave translated in Myanmar language.
On the upper reaches of the wall are stone sculptures of ogres clutching floral garlands. below are triangle shaped floral designs. at the base of the arched entrance are figures of Gonban. Keinnari and Keinnara between the lotus flowers. lion. tiger. deer. deva god. The main pillars of the devotional hall have floral designs around at the base.
Kyaukgu Umin was built into the river bank of sandstone. In the lower section were skilfully laid stone bricks and the two stories above were built of earth bricks. A maze of about 500 feet long was dug into the sand stone wall. with many twists and turns. tunnels and cellars for meditation.
Kyaukgu Umin faces north around the inside of the front main hall are niches in which eight important events of the Buddha's life are sculpted.
The large Buddha image in the main hall was hewn out of sand stone. On either side of it are relied figures of the Buddha's two disciples. on the ceiling are two Arahats in relief. each on either side of the Buddha Image.
On both sides of the inner and outer walls of the vaulted corridor in the upper storey are several square niches. in which it was originally planned to paint scenes from 550 Jatakas. It seems that the work was left unfinished.
One remarkable feature in the architecture of this monument are light wells in the vaulted hall of the first storey. From the light wells in the roof of the second storey down to the light wells of the first storey light passes through to the hall when the sun reaches noon. On the top of the entrance hall on the north side stands a small zedi.