Cheong Ek: The location of one of the many killing fields to be found around Cambodia, just 15km (9 miles) from the city. Thousands of people were executed here and there are 129 mass graves. The very moving memorial stupa contains the skulls from many of the victims found at the site.

Udong: An hour west of the city is the abandoned royal city of Udong which was the capital of Cambodia from the early 17th century until 1866, when it moved to Phnom Penh. Several temples, stupas and other buildings cover three hills. One of the stupas contains the remains of King Monivong (1927-1941).