Koh Ker comes close to what is called "capital of a forgotten empire" or "lost city in the jungle". It is Cambodia's second largest temple town. Koh Ker is of enourmous size and it would be a major attraction on the tourist worldmap if not located in the shadow of Angkor.
There are remnants of more than 180 temples in Koh Ker, in an area of more than 8,000 hectares. The number is still increasing, since more ruins have constantly being discovered in the surrounding of Koh Ker, particularly on satellite images. But plenty of land mines in this region make it difficult to explore the remote structures. However, the archaeological zone with the major monuments that are of interest for travelers can be visited without risk.
Koh Ker was located at the most important road of the Khmer empire from Angkor via Bang Melea to Preah Vihear, extending to Wat Phu in present-day South Laos and finally to the South China sea.
Koh Ker was briefly the Khmer capital during the reign of Jayavarman IV (928-942 CE). Inscriptions mentioning Koh Ker as the capital were found outside Koh Ker, too, in Siem Reap, Battambang, Kampong Cham and even in Takeo province in the very south of the empire. At least ten thousand inhabitants lived in the new capital.
Jayavarman IV had been the principal in this area and had erected monuments in Koh Ker already before ascending the throne of the entire Khmer empire. After his rival Ishanavarman II had died in Angkor, Jayavarman IV decided to continue to reside in Koh Ker. This is why it became the capital. Those days it was called Chok Gargyar "Island of Glory" and Lingapura "Phallus-city". During the reign Jayavarman's son and successor Harshavarman II the elites in Angkor managed to gain the upper hand again, and Rajendravarman II finally shifted the capital back to Angkor in 944.
Sanctuaries with Shiva-Lingams already existed already before Koh Ker became the capital. Almost all huge-scale monuments in Koh Ker were erected by Jayavarman IV, most of them even before he seized the throne of the Angkorian empire.
The first significant ruin that one comes to when approaching from Siem Reap is Prasat Pram. It is named for its five towers. Two of the towers are heavily overgrown, with roots strangling the buildings. The roots of the strangler fig of the northeastern tower are the most picturesque example of a "jungle temple" anyone can imagine.
The next structure along the Koh Ker circuit road is Prasat Neang Khmau on the right side. The temple got its name "Temple of the Black Lady" from the intriguing dark bluish colour of its laterite. The colour is the result of an oxidation process. The single tower belongs to a complex of approximately 50 metres square, enclosed by laterite walls.
The next single tower at the circuit is called Prasat Aob Neang. It is a Prasat tower built of bricks. The bricks used in Koh Ker were comparatively small and of excellent quality. As in the case of Angkor, the layers of organic mortar (of an unknown formular) are almost invisible. In the course of time, brick sanctuaries in Koh Ker proved to be more stable than the laterite constructions.
Prasat Boeung Khma is in ruins, it was a sandstone construction. Close to it, there is another ruin, a brick stone tower called Prasat Krahom. It is not to be confused with the Koh Ker's other temple of the same name, Prasat Krahom (also spelt Prasat Kraham) in front of Prasat Thom.
Prasat Damrei, "Elephant temple", is a larger shrine. Elephant sculptures at the corners of the Prasat's platform gave the name. The lions flanking the stairways are not less impressive. But only one of the eight stone lions is still at the original place at the flight of steps.
Prasat Chrap has two concentric enclosures. In the centre, three tall laterite towers stand in a row, all of them lost their facades. There are only remnants of two more brick Prasats (or maybe library buildings) facing the principal group.
Prasat Banteay Pee Chean, dedicated in 937, is one of the most picturesque monuments of Koh Ker. Though in ruins it is worth discovering. The central laterite tower was surrounded by many brick buildings, you can see nice lintel carvings on the front door of a library. Two enclosure walls with Gopuram entrance gates surround the central complex.
Prasat Krachap is in a desolate condition. Nonetheless, it is interesting because of the density of its structures, its well preserved enclosure walls, many stone carvings and inscriptions. They inform about the date of consecration, 928. Originally, Prasat Krachap had five Prasat towers in quincunx order.
Prasat Leung is a group of three huge single Prasats, all of them housing Shiva Lingas. The largest is called Prasat Leung Moi or Prasat Balang. It enshrines one of the largest and best preserved Lingam found in Cambodia. The phallus on top of a 1m Yoni, which is the stylized female genital, is 2 m high and nearly 1 m wide. The Lingam and Yoni were carved out of the bedrock.
To the south of Prasat Leung and Prasat Thom, the 1,200 m long and 550 m wide Baray reservoir called Rahal, now dried up, was right in the centre of the city. The laterite embankments are the largest structure in Koh Ker.
Trapeang Andong Preng, 200 m south of Prasat Thom, is often filled with water. The 40 m long Trapeang has steps of laterite. Supposedly it was the Royal Bath, located close to the Royal Palace, which was built of perishable materials and disappeared.
The principal structure of Koh Ker is Prasat Thom, buiIt already before Koh Ker became the capital. It forms a prestigious procession way towards the pyramid called Prang. The alley connects two complexes, the first one being an enlarged entrance, the inner one an ensemble of nine Prasat towers surrounded by an impressive moat. The next compound includes the temple pyramid Prasat Prang. This layout is not the usual concentric one, it is linear. This means, the complexes are arrayed in a line, one after another instead of inner courtyards surrounded by outer ones. A few decades later on, parts of this layout were copied by the most lovely Khmer temple, Banteay Srei.
More accurately, Prasat Thom (as well as Banteay Srei) can also be described as a combination of linear and concentric layout, since Prasat Thom shows a quite common scheme of three concentric enclosures, too. The first (inner) and the second enclosure walls are on the artificial island, the second one runs along the wide moat, which is surrounded by the third (outer) enclosure wall. In this perspective, the complex outside the temple island can be interpreted as an enormously enlarged Gopuram entrance gate of that third enclosure wall.
This outer complex in the row of compounds is called Prasat Krahom (or Prasat Kraham), the "Red Temple". Only the concentric complex on the island is Prasat Thom in a narrow sense. The red brick tower of Prasat Krahom is a temple on its own and a Gopuram gate for Prasat Thom at the same time. Fragments of a huge Shiva statue were found in this red tower, the hands are exhibited now in the National Museum in Phnom Penh. The alley mentioned above begins here and leads across the dam. Prasat Thom (in a narrow sense) is then reached by a Naga-flanked causeway. Prasat Krahom was once known for its carved lions, but almost none of them remain today.
The core structure of Prasat Thom, on that island inside the moat, consists of nine towers arranged in 2 rows on a single platform. Long narrow buildings of the second enclosure almost form a gallery.
A Sanskrit inscription at Prasat Thom mentions the consecration of a Shiva-Lingam called Tribhuvaneshvara ("Tree World's Lord") in 921, this means, already before Jayavarman IV ascended the throne and Koh Ker became the capital. This is remarkable as such a Lingam usually was identified with a king and symbolized imperial power.
Prasat Prang, Koh Ker's landmark, is a 62 m wide and 35m high sandstone pyramid with seven levels. It is integrated into the linear layout of Prasat Thom. Prasat Prang is the Khmer monument that seems to be most similar to mesoamerican step pyramids. Most probably, it was the place of King Jayavarman IV's state idol, the Lingam Tribhuvaneshvaram mentioned above, since an inscription at Prasat Damrei mentions that a Lingam of about 4.5 m was erected on top of a Prang.
Under Jayavarman IV the art of sculpture reached a pinnacle. Statues in the style of Koh Ker belong to the most celebrated of Asia because of their vividness and expressiveness. They fetch record-breaking amounts on auctions. Many of the Koh Ker sculptures were stolen. Most of the remaining statues are in museums and private collections now.