Mỹ Sơn (Vietnamese pronunciation: [mǐˀ səːn]) is a cluster of abandoned and partially ruined Hindu temples constructed between the 4th and the 14th century AD by the kings of Champa (Chiêm Thành in Vietnamese). The temples are dedicated to the worship of the god Shiva, known under various local names, the most important of which is Bhadreshvara. Mỹ Sơn is located near the village of Duy Phú, in the administrative district of Duy Xuyên in Quảng Nam Province in Central Vietnam, 69 km southwest of Da Nang, and approximately 10 km from the historic town of Trà Kiệu. The temples are in a valley roughly two kilometers wide that is surrounded by two mountain ranges.
From the 4th to the 14th century AD, the valley at Mỹ Sơn was a site of religious ceremony for kings of the ruling dynasties of Champa, as well as a burial place for Cham royalty and national heroes. It was closely associated with the nearby Cham cities of Indrapura (Đồng Dương) and Simhapura (Trà Kiệu). At one time, the site encompassed over 70 temples as well as numerous stele bearing historically important inscriptions in Sanskrit and Cham. Mỹ Sơn is perhaps the longest inhabited archaeological site in Indochina, but a large majority of its architecture was destroyed by US carpet bombing during a single week of the Vietnam War. The Mỹ Sơn temple complex is regarded one of the foremost Hindu temple complexes in Southeast Asia and is the foremost heritage site of this nature in Vietnam. It is often compared with other historical temple complexes in Southeast Asia, such as Borobudur of Java in Indonesia, Angkor Wat of Cambodia, Bagan of Myanmar and Ayutthaya of Thailand. As of 1999, Mỹ Sơn has been recognized by UNESCO as a world heritage site. At its 23rd meeting, UNESCO accorded Mỹ Sơn this recognition pursuant to its criterion C (II), as an example of evolution and change in culture, and pursuant to its criterion C (III), as evidence of an Asian civilization which is now extinct.