The head temple of the Mohanikay order and the seat of Cambodia's Supreme Buddhist Patriarch, Wat Ounalom faces the Tonle Sap River just north of the Royal Palace. The complex was largely destroyed by the Khmer Rouge in the 1970s — most of the monks were killed and the library burned — and the current buildings reflect a long, patient restoration.
The main stupa is said to contain an eyebrow hair of the Buddha (ounalom means "eyebrow"), and the second-floor sanctuary holds a marble Buddha that survived the Khmer Rouge thanks to monks who hid it. Worth combining with a walk along Sisowath Quay.