74 previously unknown medieval churches and a complex irrigation system were found in Cambodia around the famous monument of ancient art of Khmer Angkor Wat. The new card of the historic district, sprawling for 100 sq km, is published in the journal "Proceedings of the National Academy of Sciences" of USA. Authors-compilers - are an international group of scientists from Australia, France and Cambodia. In their work they used aerial photography and satellite and radar research NASA. As explained in an interview with BBC News Damian Evans (Damian Evans) from the University of Sydney (University of Sydney), «radar detects topographical deviations, the difference in vegetation cover and moisture content up to 1 meter. Thus able to penetrate through the undergrowth, hiding one of the UNESCO World Heritage site.

And it turns out that the medieval settlement surrounding Angkor, the capital of the Khmer empire from 9 to 14 age, is 3 times bigger than expected. According to the latest data Angkor Wat covers an area of 3 000 sq km, it is the largest of its kind, a set of pre-industrial era. Only Tikal can be compared with it, Mayan city in Guatemala, it covers about 150 square kilometers.

According to new calculations, Angkor Wat could support life of about half a million people. At the same time, as noted by Agency France-Presse, the irrigation system could cause the fall of the Khmer civilization in the 14 century. "We saw the dams, which underwent destruction and were restored by bridges and dams, therefore, at times the system was unmanageable" - says Evans. Disappearance of the Angkor, according to scientists, could also contribute to deforestation, overpopulation and erosion of topsoil. The town was fairly large, it had fairly intensive agriculture, and all this could lead to serious environmental problems - an Australian researcher says.