Cambodia is bordered by three countries, Vietnam to the East, Laos to the North and Thailand to the West. Therefore, there are three different border crossings you can use to enter the country and three different directions to travel through the country. There is no set route through Cambodia and each way is just as popular as the next.
It's easy to combine a trip to Vietnam with a visit to Cambodia. If you are entering Cambodia from Vietnam, you will cross the border at Chau Doc and continue onto the capital of Cambodia - Phnom Penh. Phnom Penh is a modern city with paved roads and modern stores. It's easy to spend a few days in Phnom Penh soaking up the lively atmosphere. You could also visit the Tuol Sleng Museum and the Killing Fields, a reminder of Cambodia's troubled past under the rule of Pol Pot and the Khmer Rouge. From Phnom Penh you can continue to head west to Siem Reap, by boat if you are adventurous. The boat trip along the Tonle Sap river offers the chance to watch the world go by slowly with views of life along the river bank. When you reach Siem Reap make sure you visit the world famous Angkor Wat. Most people take at least two days to see Angkor Wat, and don't forget to set your alarm for the sunrise over the temples - a definite 'must see'. From Siem Reap, you can continue travelling westward to cross the border into Thailand at Poipet. This trip can be done in reverse as well - starting in Thailand and travelling east through Cambodia into Vietnam.
If Laos is first on your itinerary, you would enter Cambodia from the north, at the border crossing town of Veunkham. Travellers will not be able to get a visa on arrival at this border crossing, so make sure you have your Cambodia visa organised beforehand. You'll be travelling along the famous Mekong River from Laos into Cambodia, to a town called Stung Treng. Stung Treng is a quiet town far away from the tourist towns. It's quite basic and you will really feel like you are experiencing the real country. From Stung Treng you can again travel along the mighty Mekong river towards Kratie, which is home to the rare fresh water dolphin, the Irrawaddy. The best time to spot these dolphins is either early in the morning, or at the end of the afternoon as the sun is going down. After Kratie, you can travel by bus to the nation's capital Phnom Penh. This cosmopolitan city is easy to get around and has lots of historic buildings. From Phnom Penh you can continue on towards Vietnam to the south, via Chau Doc, or you could continue in the opposite direction towards Thailand. As a side trip from Phnom Penh, you could also continue travelling south in Cambodia and visit the beach side towns of Sihounkville and Kep. Sihounkville is more developed than Kep, but the beaches at both towns are a welcome relief from the tropical climate inland.
It's popular to combine Vietnam and Cambodia and a lot of people travel from Saigon, along the Mekong River, cross the border at Chau Doc and continue onto Phnom Penh. And a visit to Cambodia is not complete without seeing the Angkor Wat, particularly at sunrise. Just remember to set your alarm clock.
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