Oudong is a former town of the post-Angkorian period (1618–1863) situated in present-day Phsar Daek Commune, Ponhea Lueu District, Kandal Province, Cambodia. Located at the foothill of the mountain Phnom Oudong, also known as Phnom Preah Reach Troap, about 35 km northwest of the modern capital Phnom Penh via National Road No. 5, Oudong was a royal residence and Cambodia's capital for almost 250 years until 1866. A monumental royal necropolis of sovereigns of several centuries is scattered on top of the prominent bisected mountain, which runs from the southeast to the northeast.

Kandal is a province of Cambodia located in the southeast portion of the country. It completely surrounds the Cambodian capital of Phnom Penh and borders the provinces of Kampong Speu and Takéo to the west, Kampong Chhnang and Kampong Cham to the north, Prey Veng to the east, and shares an international border with Vietnam to the south. It is the second most populous province in Cambodia after the capital Phnom Penh. Its capital and largest city is Ta Khmau, which is approximately eight kilometres (5.0 mi) south of central Phnom Penh. Kandal is one of the wealthier provinces in the country.