Up the hill: Phnom Bakheng

The oldest temple in the site, Phnom Bakheng is best known as a sunset viewing spot. Visit at other times of the day, and you'll find a quiet, simple temple, built on top of a hill.

Much of the original temple is gone, leaving behind a large flat surface topped with a handful of towers. When I visited there was also a lot of construction / restoration going on the site, and the trees on the hill were getting tall enough to block most of the views. 

But all that said, it's a still a nice walk up the hill, underneath the trees.