The temple complex at Angkor Wat, just outside of Siem Reap, Cambodia, is world famous for its intricate lotus-blossom towers, its enigmatic smiling Buddha images and lovely dancing girls (apsaras), and its geometrically perfect moats and reservoirs.
An architectural jewel, Angkor Wat itself is the largest religious structure in the world. It is the crowning achievement of the classical Khmer Empire, which once ruled most of Southeast Asia. The Khmer culture and the empire alike were built around a single critical resource: water.
The connection with water is immediately apparent at Angkor today. Angkor Wat (meaning "Capital Temple") and the larger Angkor Thom ("Capital City") are both surrounded by perfectly square moats. Two five-mile-long rectangular reservoirs glitter nearby, the West Baray and the East Baray. Within the immediate neighborhood, there are also three other major barays, and numerous small ones.
Some twenty miles to the south of Siem Reap, a seemingly inexhaustible supply of freshwater stretches across 16,000 square kilometers of Cambodia. This is the Tonle Sap, Southeast Asia's largest freshwater lake.
It may seem odd that a civilization built on the edge of Southeast Asia's "great lake" should need to rely on a complicated irrigation system, but the lake is extremely seasonal. During the monsoon season, the vast amount of water pouring through the watershed causes the Mekong River to actually back up behind its delta, and begin to flow backwards. The water flows out over the 16,000 square kilometer lake-bed, remaining for about 4 months. However, once the dry season returns, the lake shrinks down to 2,700 square kilometers, leaving the Angkor Wat area high and dry.
The other problem with Tonle Sap, from an Angkorian point of view, is that it is at a lower elevation than the ancient city. Kings and engineers knew better than to site their wonderful buildings too close to the erratic lake/river, but they did not have the technology to make water run uphill.
In order to provide a year-round supply of water for irrigating rice crops, the engineers of the Khmer Empire connected a region the size of modern-day New York City with an elaborate system of reservoirs, canals and dams. Rather than using the water of Tonle Sap, the reservoirs collect monsoon rainwater, and store it for the dry months. NASA photographs reveal the traces of these ancient waterworks, hidden at ground level by the thick tropical rainforest. A steady water supply allowed for three or even four plantings of the notoriously thirsty rice crop per year, and also left enough water for ritual use.
According to Hindu mythology, which the Khmer people absorbed from Indian traders, the gods live on the five-peaked Mount Meru, surrounded by an ocean. To replicate this geography, the Khmer king Suryavarman II designed a five-towered temple surrounded by an enormous moat. Construction on his lovely design began in 1140; the temple later came to be known as Angkor Wat.
In keeping with the aquatic nature of the site, each of Angkor Wat's five towers is shaped like an unopened lotus blossom. The temple at Tah Prohm alone was served by more than 12,000 courtiers, priests, dancing girls and engineers at its height - to say nothing of the empire's great armies, or the legions of farmers who fed all the others. Throughout its history, the Khmer Empire was constantly at battle with the Chams (from southern Vietnam) as well as different Thai peoples. Greater Angkor probably encompassed between 600,000 and 1 million inhabitants - at a time when London had perhaps 30,000 people. All of these soldiers, bureaucrats and citizens relied upon rice and fish - thus, they relied upon the waterworks.
The very system that allowed the Khmer to support such a large population may have been their undoing, however. Recent archaeological work shows that as early as the 13th century, the water system was coming under severe strain. A flood evidently destroyed part of the earthworks at West Baray in the mid-1200s; rather than repairing the breach, the Angkorian engineers apparently removed the stone rubble and used it in other projects, idling that section of the irrigation system.
A century later, during the early phase of what is known as the "Little Ice Age" in Europe, Asia's monsoons became very unpredictable. According to the rings of long-lived po mu cypress trees, Angkor suffered from two decades-long drought cycles, from 1362 to 1392, and 1415 to 1440. Angkor had already lost control of much of its empire by this time. The extreme drought crippled what remained of the once-glorious Khmer Empire, leaving it vulnerable to repeated attacks and sackings by the Thais.
By 1431, the Khmer people had abandoned the urban center at Angkor. Power shifted south, to the area around the present-day capital at Phnom Pehn. Some scholars suggest that the capital was moved to better take advantage of coastal trading opportunities. Perhaps the upkeep on Angkor's waterworks was simply too burdensome.
In any case, monks continued to worship at the temple of Angkor Wat itself, but the rest of the 100+ temples and other buildings of the Angkor complex were abandoned. Gradually, the sites were reclaimed by the forest. Although the Khmer people knew that these marvelous ruins stood there, amidst the jungle trees, the outside world did not know about the temples of Angkor until French explorers began to write about the place in the mid-nineteenth century.
Over the past 150 years, scholars and scientists from Cambodia and around the world have worked to restore the Khmer buildings and unravel the mysteries of the Khmer Empire. Their work has revealed that Angkor Wat truly is like a lotus blossom - floating atop a watery realm.
Photo Collections from Angkor:
Various visitors have recorded Angkor Wat and surrounding sites over the past century. Here are some historic photos of the region.
French Ministry of Foreign Affairs photos from 1866.
Margaret Hays' photos from 1955.
National Geographic/Robert Clark's photos from 2009.
Plan your own adventure travel to Angkor Wat.
Angkor and the Khmer Empire, John Audric. (London: Robert Hale, 1972).
Angkor and the Khmer Civilization, Michael D. Coe. (New York: Thames and Hudson, 2003).
The Civilization of Angkor, Charles Higham. (Berkeley: University of California Press, 2004).
"Angkor: Why an Ancient Civilization Collapsed," Richard Stone. National Geographic, July 2009, pp. 26-55.