Candi Asu is part of the Sengi complex built in the 8th and 9th centuries. It is a Hindu temple lying between Central Java and Yogyakarta. It is nestled in between Mount Merapi and Mount Merbabu volcanoes and nearby the road from Mungid to Boyolali. An external wall is formed as the base with an internal wall acting as the foundation. Between the two walls, the area has been filled with 2 meters of rocks and earth then paved on the top. The remaining space was left for a center statue to be placed. On the western outside wall, a masonry mass was left, forming the stairs. From this rough layout, new lines were drawn in the paving in order to expand and build the temple properly. Angular rocks were used as the original blocks were setting at an angle. The temple was neari lik pieon and larger rocks were to be placed last. Carving began from the top of the temple, working downward. The large finishing rocks that were to be used at the end where never carved or used, offering an explanation to their disappearance from the site.
- Dumarçay, Jacques (1978). edited and translated by Michael Smithies, "Borobudur", p. 47. Oxford University Press. ISBN 978-0-19-580379-2.