Udong (ឧដុង្គ, literally, 'victorious') served as the capital of Cambodia under several sovereigns between 1618 and 1866, during which time ‘victorious’ was an optimistic epithet, as Cambodia was in terminal decline. A number of kings, including King Norodom, were crowned here. The main attractions today are the twin humps of Phnom Udong (ភ្នំឧដុង្គ), which have several stupas on them. Both ends of the ridge have good views of the Cambodian countryside, dotted with innumerable sugar-palm trees.
The larger main ridge – the one you’ll hit first if approaching from NH5 – is known as Phnom Preah Reach Throap (ភ្នំព្រះរាជទ្រព្យ; Hill of the Royal Fortune). It is so named because a 16th-century Khmer king is said to have hidden the national treasury here during a war with the Thais.
Phnom Udong really fills up with locals at weekends but is quiet during the week. Admission is free.