Built around 1060 by the ruler Udayadityavarman II in honor of the god Shiva, this temple-mountain is located northwest of Bayon, just before the Royal Palace. This five-story pyramid is 34 meters high and is made of 300,000 blocks of stone (each weighing 500 kg!). A real feat of the architects of the time as well as the workers working on the site. It was once called svarnadri, "the mountain of gold"; it is assumed that each of the bas-reliefs representing the epic of the Ramayana were covered with copper or gold plates, so that the Baphuon would resemble Mount Meru, the mythical mountain representing the center of the universe. In the sanctuary at the top of the building was a linga, probably made of gold. The temple then underwent several modifications; the most famous and the most visible: the entire western facade of the temple was transformed in order to carve a giant reclining Buddha, probably in the 15th century.

If we can't see much of it today, it's the fault of the architects of the time. Many defects have marred the construction. The main one: the artificial hill that supports the whole is made of sand, which makes the base extremely unstable. The French archaeologist B.-P. Groslier then decided to dismantle the temple block by block and to reconstitute it once the foundations were solidified: an anastylosis that was to last 10 years. The Khmer Rouge interrupted the work and the files referencing the 300,000 blocks of stone, then piled up in the jungle not far from the site, were lost. It was not until 1995 and a small computer genius to put back in place all these large stones, thanks to a revolutionary software. The idea was to propose a model of the temple which took into account each piece found by the archaeologists, and capable of analyzing the archive photos. The archaeologists were thus able to create a gigantic 3D puzzle on a computer, in order to better understand the challenges of this extraordinary restoration. The Cambodian workers of the Ecole Française d'Extrême-Orient have thus completed in 2011 a titanic renovation project that has allowed the restoration of this Golden Mountain. This temple is definitely a must-see during a visit to Angkor Thom: not only are magnificent bas-reliefs (mainly of animals and the Ramayana) still visible, as well as the silhouette of the reclining Buddha, but above all because tourist groups hardly stop there. Once at the top of the pyramid, the view is splendid and the calm is precious.