Roluos Group comprises of three temples; Preah Ko, Bakong, and Lolei. The temples are located about 4 km from Tonle Sap Lake and 13 km from Siem Reap. The area was once the capital of Khmer Kingdom in the late 9th century after King Jayavarman II moved the city from Mount Kulen. The three surviving temples are distinguished by designs and construction materials – they are the only buildings in Siem Reap that are made of bricks. Even though several sections of the temples are in dilapidated state, they are well preserved and worth a visit.

Preah Ko temple, which means sacred bull in Cambodian language, has the statues of bulls in front of the main towers. The carved decoration on the sand stone doors, lintels and columns of the towers is exquisite. Lolei temple features well preserved carved lintels and is guarded by sculpted stone lions. Bakong temple is the most impressive temple of Roluos Group. Built in the 9th century, it is the first temple mountain built in sandstone. Its architectural style became a prototype that was used in building temple mountains for the next 400 years. The temple is built on a manmade hill and protected by two separate enclosure walls. It is accessible by causeways and wealth in decorations of sculpted animal figures and finely carved lintels.