The panels were discovered by local secondary school students on a field trip as they crossed the Opak River in Ngablak, Sleman, about one kilometer from the Sewu and Prambanan temple complexes.
Sewu is an 8th-century Buddhist temple, and the second-largest Buddhist temple in Central Java after Borobudur. It is located less than a kilometer north of Prambanan, a ninth-century Hindu temple.
Paryono, the school’s principal, said the students were drawn to inspect the unusual rocks. “They were everywhere along the river and embankment,” Paryono said.
He said that while some of the stones were carved, others looked like ordinary rocks.
“Some had carvings like the stones on a temple,” Paryono said, adding that the school had immediately reported the discovery to the preservation agency.