The architecture of the Khmer empire of Angkor: temple-mountains of sandstone and laterite, with towers in a quincunx on stepped terraces, concentric galleries, moats and causeways, culminating in Angkor Wat.
Indian religion, script and architectural ideas reached mainland Southeast Asia in the first centuries AD along the trade routes. In 802 Jayavarman II proclaimed himself universal monarch in the Kulen hills north of the Tonle Sap lake, and for more than six centuries his successors ruled an empire from the region of Angkor, where they built a succession of capitals and hundreds of temples, served by a vast system of reservoirs (barays) and canals.
The Khmer temple is a shrine tower (prasat) of brick or sandstone on a square, redented plan, with doors, real or false, on four sides and a tower of diminishing tiers. From the ninth century the kings built state temples as temple-mountains, images of Mount Meru, the axis of the Hindu and Buddhist universe: at the Bakong (881) a stepped pyramid carries a single tower; at Pre Rup (961) and Ta Keo (c. 1000) five towers stand on the summit in a quincunx, the four corner towers and the central one repeating the five peaks of Meru. Around the mountain run concentric walls and moats, the ranges and oceans that surround the world.
Angkor Wat, built for Suryavarman II in the first half of the twelfth century and dedicated to Vishnu, is the largest religious monument in the world. Its moat, some 190 metres wide, encloses a rectangle of about 1.5 by 1.3 kilometres; a causeway lined with naga balustrades leads from the west to the temple, which rises in three galleried terraces to the quincunx of lotus-bud towers, the central one 65 metres above the ground. The outer gallery carries several hundred metres of continuous bas-relief. Unusually, the temple faces west, which has been linked both to Vishnu and to a funerary purpose.
Khmer builders never used the true arch; their galleries are covered by corbelled vaults, and their spans are therefore narrow. They compensated with length, repetition and height, and with sculpture of the greatest refinement: the devatas and apsaras on every wall, the pink sandstone carvings of Banteay Srei (967). Under the Buddhist king Jayavarman VII, around 1200, the Bayon at the centre of Angkor Thom multiplied the towers into a forest of faces. After the sack of Angkor by Ayutthaya in 1431 the capital moved south, but Angkor Wat remained a place of pilgrimage and never entirely fell out of use.