From the World Heritage inscription:
Angkor is one of the most important archaeological sites in South-East Asia. Stretching over some 400 km2, including forested area, Angkor Archaeological Park contains the magnificent remains of the different capitals of the Khmer Empire, from the 9th to the 15th century. They include the famous Temple of Angkor Wat and, at Angkor Thom, the Bayon Temple with its countless sculptural decorations. UNESCO has set up a wide-ranging programme to safeguard this symbolic site and its surroundings.
I could spend a month at Angkor and fill every day taking photos. There were hundreds of photos I could have taken if I was only at a place at a different time of day.
Most people only think of Angkor Wat and assume that temple is all there is to see. The entire Angkor complex is enormous and encompasses many square kilometers, not including the many smaller temples on the outskirts of Sieam Reap. People still live on the grounds of Angkor and make a living selling things to tourists (often annoyingly so).
I spent about four days exploring Angkor and I could go back today and see things I didn’t see my first time around.