While I was in Kampot, I signed up to go on a tour of the Bokor Hill Station. This used to be a French lookout post, located at the top of the highest hill in the neighbourhood. It was finally abandoned after fighting with the Vietnamese in the mid-60s, and hasn't been used since then.
The road up to the hill station was paved... sometime in the 60s. The tour involves a 4x4 truck equipped with benches along the sides of the bed, and a bar down the middle which you grab to hang on. This road was probably the worst road I've ever seen, including all the ex-logging loads in B.C. We had to pull out two other trucks that had gotten stuck. It didn't help that the soil was mostly clay, slickened by recent rains.
When we got to the top, we mostly wandered in a thick fog, which added a lot to the atmosphere of the place. Startlingly bright orange moss growing out of all the crevices, crumbling tile, light fixtures hanging down, stifling humidity, and a palpable absence of any recent human influence.