A baray is a vast rectangular reservoir formed by raised embankments rather than by damming a valley, orientated to the cardinal points and set within a network of canals, moats, dykes and distribution channels running from the Kulen hills to the Tonle Sap. Yasovarman I built the East Baray (Yasodharatataka) around 900 CE at some 7.5 by 1.8 km; the later West Baray held tens of millions of cubic metres. The system captured monsoon runoff, controlled flooding, recharged groundwater and supported dry-season rice, while embankment roads doubled as the city's circulation. Temple-mountains stood on the axes as the cosmological centre of the water figure.
Angkor is the largest low-density pre-industrial urban complex known — a settlement of perhaps 700,000 people dispersed across roughly 1,000 sq km whose structure was set by hydraulic works rather than walls. It shows infrastructure, cosmology and agriculture designed as a single spatial system, and its silting and channel failure is a standard case study in infrastructural collapse. It remains the reference case for water-structured, dispersed urbanism outside the Western canon.
See it on the timeline →