Built by successive Khmer kings between the 9th and 14th centuries, the magnificent Angkor temple complexes represent the jewel in the crown of Khmer civilisation. Based on religious concepts adapted from India, Angkor and its components were created as models of the universe. A complex system of reservoirs, canals and moats served the practical purpose of irrigation but also reflected the symbolic concept of an ocean surrounding a central mountain. Covering an area of more than 400 square kilometres, the site boasts more than 100 monuments, of which two dozen are major temples. Abandoned for three centuries and reclaimed by the jungle, these monuments were ‘rediscovered’ by French naturalist Henri Mouhot in 1861, although the Khmers had used them continuously over the centuries for religious purposes. Angkor Conservancy was established in 1907 and the École Française d’extrême-orient (EFEO) began restoring the monuments in 1908. However, because of the extremely large scale of the monuments and the two world wars, the Indochina War and then the civil war in Cambodia from 1974, full-scale preservation and restoration could not be undertaken. Since the Angkor monuments are built mainly of sandstone, they have been continuously damaged by the harsh climate, wind and rain, not to mention being further ravaged by the invasion of trees and other vegetation. In 1993 Angkor was placed on the UNESCO World Heritage List and an international committee known as the International Co-ordinating Committee for the Safeguarding and Development of the Historic Site of Angkor (ICC) was established to administer the site. Since 1995 a Cambodian government authority known as APSARA (Autorité pour la Protection du Site et l'Aménagement de la Région d'Angkor/Siem Reap) has taken charge of security, development and restoration at the site. Restoration is currently being undertaken by various international conservation agencies – most notably the École Française d’extrême-orient (EFEO), the German Apsara Conservation Project (GACP), the Japanese Government Team for Safeguarding Angkor (JSA) and the World Monuments Fund (WMF) – which are all members of the ICC but report to UNESCO. There follows a list of the more important sites - admission to all sites except Beng Melea, Kbal Spean and Phnom Kulen is via a single ticket.