In March 2016 we took an organised tour to Indochina visiting Vietnam (the main part of the holiday) as well as Laos and Cambodia. Three very different countries.
We flew in to Siem Reap which is the tourist town for the nearby Angkor complex of temples. Siem Reap consists of newly built hotels & restaurants & little else. On the first night we walk the short distance to the Trip Advisor top rated restaurant in the town for a great "fusion" meal. In the short walk to this restaurant we pass flashy, newly built opulent hotels - but no money has been spent on the non-existent pavements.
Needless to say that the Angkor complex of temples were absolutely stunning.
Phnom Penh was not a memorable capital city. It is still haunted by the Cambodian genocide of the late 1970's.