Angkor National Park, national park in northwestern Cambodia. Established in 1925, the park covers 160 sq km (60 sq mi) of rain forest terrain. It was created by the French colonial authorities to protect the ruins of the former capital city of the Khmer Empire, the first Cambodian state. Between the late 9th century, when it was known as Yasodharapura, and the early 13th century, when it was known as Angkor Thum, the city was both a royal and religious center. Its best-known structures are Angkor Wat, a Hindu temple constructed in the early 12th century, and Bayon, a Buddhist temple completed in about 1215. Each of these was the main structure within complexes of monuments, canals, and reservoirs. These complexes represented the shape of the universe according to the religious beliefs of the kings who had them built, Suryavarman II and Jayavarman VII, respectively.

Angkor was abandoned as the Cambodian capital in 1431, but Angkor Wat was turned into a Buddhist temple and remained in use. French archaeologists began uncovering the jungle-laden Angkor site in 1863, and for nearly a century thereafter the French conducted an extensive project of reconstruction and research. During the political and military upheavals of the 1970s and 1980s, however, the restoration effort was put on hold and the Angkor site was damaged, pillaged, and neglected. In 1987 the Archaelogical Survey of India began a seven-year restoration project on the Angkor Wat complex. Since 1991 the United Nations Educational, Scientific, and Cultural Organization (UNESCO) has helped the Cambodian government coordinate an international effort to research and preserve the sites in Angkor National Park.