Dating back to 1443, this monument Buddhist temple compound was one of the original five temples in Phnom Penh and serves as the headquarters of Cambodian Buddhism. It was heavily damaged during the Khmer Rouge period but has since been restored.

The temple gets its name from its role as repository for an "ounalom," a hair from the Buddha’s eyebrow, said to be contained in the large chedi behind the vihara (monastery).

The monks use the vihara in the early morning, after which time visitors can enter.