A trip proposal plan to Cambodia
If you come from any country of Europe, I would recommend you to take a flight to Bangkok. Then do not take the flight directly to Phnom Penh, but to Siem Reap Airport. Traveling back to your country, book your flight not from Siem Reap, but from Phnom Penh Airport. In this way, after visiting Siem Reap and the Angkor Wat sites, you go to Phnom Penh and visit the south of the country.
If you come from US, Canada or Latin America, take a flight to Japan, Taiwan or Hong Kong. Then from there to Siem Reap Airport. Coming from Latin America, is would be cheaper to go through any US airport.
Siem Reap / Angkor Wat
You will need about three days as minimun to visit the Angkor temples of Siem Reap. It is worthy of. If you want to stay the week, if you like archaeology, you will not lose time. Buy the Angkor ticket for three days better. There is for one day stay and for three days stay.
Siem Reap is also a city with a busy nightlife. Day in the temples, night in the clubs.
Do not forget the lake, the dawns and the pagodas.
Sambor Preikuk / Kompong Thom
This archaeological site is very often forgotten. It is located midway between Siem Reap and Phnom Penh, in the Kompong Thom province. Sambor Preikuk is a group of pre-Angkorian temples of an indescribable beauty and interest. You have to reach Kompong Thom downtown and from there, the trip by car will take about half an hour by an unpaved road. The region is beautiful. A day and a night would be enough to stay in Kompong Thom.
Phnom Penh / Sihanoukville
Here you reach the capital, almost 2 million inhabitants and a growing center. You can visit the trace of the wars, especially the Khmer Rouge regime with the museums like Tuol Sleng, but also the religious complexes and the Royal Palace. Also Phnom Penh have a busy nightlife to see and relaxing areas along the river.
From Phnom Penh you can arrange your tour to Sihanoukville. A day and a night in the coastal town is enough. But if you like sea nature, the region will offer you islands, beaches, a national park with a wonderful tropical jungle, hills and the most beautiful views of Cambodia, especially the evenings.
You can travel from Sihanoukville to Kep City, two hours by car to the east, near the Vietnamese border. Another day in the beaches and go back to Phnom Penh. That is why you can book your flight back from Phnom Penh, so you do not need to make another six hours back to Siem Reap.
Then there is the option to take the Phnom Penh – Ho Chi Minh City (Saigon) bus. It would take you there in about six to eight hours.