Hidden in a lonely ravine between the Petanu and Pakrisan Rivers, the ruins of this unique 14th-century rock relief lay buried for centuries under volcanic eruptions and vegetation. The site was excavated by Dutch authorities in 1925 and in 1949, a stone gutter was cemented on top in order to drain off water, to prevent erosion and vegetation from taking hold, revealing even more of the stone mural.

Once a vibrant and influential hub, this ancient metropolis was founded in 1350 by U-Thong (later crowned Ramathibodi I) and became the...