Preah Vihear is a 9th century Hindu temple built before the Angkor temples and later converted to Buddhism. This is the most holy Buddhist site in Cambodia and can be busy with mostly Cambodian visitors on government holidays. It is about 200 kilometers away from Siem Reap on the border of Cambodia and Thailand. Because of the distance from Siem Reap, there are very few tourists. I didn't see a single one until near the end of my visit. The temple is on top of a 525-meter (1,722-foot) cliff with amazing views of Cambodia and Thailand.