Phnom Udong - រមនីដ្ឋាន ភ្នំឧត្តុង្គ

Oudong (Khmer: ឧដុង្គ) (also romanized as Udong or Odong) is a town in Cambodia, situated in the north-western part of Kampong Speu Province. Located at the foothill of the mountain Phnom Udong, about 40 km northwest of the modern capital Phnom Penh, Oudong was royal residence and Cambodia's capital for more than 250 years until 1866. A monumental royal necropolis of sovereigns of several centuries is scattered on top the prominent bisected mountain, which runs from the southeast to the northeast.
Oudong was founded by King Srei Soryapor in 1601, after the abandonment of Longvek. Under the reign of King Ang Duong (1841-1850), he constructed canals, terraces, bridges and erected hundreds of pagodas in this region. Oudong was later abandoned by King Norodom in 1866 in favor of Phnom Penh.
From 1618 until 1866 it was formally called Oudong Meanchey, home to a succession of kings deposed from the former capital of Lovek by the invading Thais. In 1866, it was abandoned by King Norodom, taking his royal court along with him to the current capital, Phnom Penh. It was extensively damaged by the Khmer Rouge in 1977, along with the other temples, monuments, and religious structures there.