Angkor Wat
The centerpiece not only of the Angkor Archaeological Park, but of Khmer civilization. Tends to be most crowded late in the afternoon but that's also the best time to photograph the temple as the late afternoon sun can bring out a pleasant golden glow to the temple. I tried to be there for both times of the day. However, my evening tour got rained on. Morning and mid-day the sun's positioning renders Angkor Wat as a grey outline, but you can walk around the galleries studying the bas-reliefs. There are steep steps to the top and be sure not to touch any carvings.
