Transportation
Bullet Boats
This is a nice option for you travel along the Mekong. Phnom Penh to Kampong Cham takes two hours and costs 10,000 riel. The boats depart just north of the Japanese Bridge (around 150m) on the Phnom Penh side of the Tonle Sap River. Kampong Cham to Kratie is a three hour boat ride and the cost is about 15,000 riel. The boats usually do not continue on to Stung Treng, as the water level must be very high to enable the boats to clear all of the small islands and clumps in the river between Kratie and Stung Treng. The boats usually don't even go during the rainy season, as there aren't many people travelling on this route.
Bikers
The cost for taking a motorcycle with you by boat for a section of the trip is the same price as for a person. It's not recommended, though, as the porters who load and unload the boats are a hassle to deal with and if they happen to drop your motorcycle in the river (a real possibility), it's your loss and not theirs. If you have a motorcycle, ride it. It's not recommended to combine the two modes of transportation.
Buses or Vans
There are many Bus companies like Giant Ibis, Mekong Express, PSD Xpress, Sorya Bus, Neak Krohorm, Thero Express (15-seat), Larryta, KSO, Virak Buntham, Kampot Express, Cambodia Post VIP Van offering bus/van services to Kampong Cham town using modern air-conditioned buses/vans. Buses/vans depart every 15 minutes to one hour, daily from 6am-12pm mid night. The prices are reasonable.
Online Bus ticket can be purchased in advance.
Featured bus/van to Kampong Cham:
Share Taxis
As it is quite cheap and quick with the air-con buses from Phnom Penh to Kampong Cham, there is not much of a reason to take a taxi. A share taxi from Kampong Cham to Kampong Thom is 8,000 riel. The road is in good condition. The share taxi do not go all the way to Kratie at this time, only as far as Snoul, the small town that is the juncture point for the road to Kratie and to Sen Monorom town in Mondulkiri Province. In Snoul there are only sometimes share taxis plying the route to Kratie. If you don't have your own motorcycle as transportation, your surest bet is to take the bullet boat if you want to go to Kratie from Kampong Cham.
Phnom Penh to Kampong Cham
As mentioned earlier, the highway from Phnom Penh is in excellent condition; you take Highway No 6 from Phnom Penh (crossing the Japanese Bridge) and go to the roundabout in Skun comprising a stature of children holding a bird. Highway 6 continues on to the left, going to Kampong Thom and Siem Reap. For Kampong Cham, you veer to the right and follow Highway No 7. A scenic option to this is to follow the river road on the eastern side of the Mekong River (if own vehicle). It takes a bit more time but if you have time it's worth it. Security is not a problem. Until the new bridge over the Mekong River is finished, you still take the big ferry across if you want to explore the eastern side of the province or continue on to Kratie or Mondulkiri Provinces by motorcycle or vehicle. It's 200 riel per person and 400 riel for a motorcycle.
Kampong Cham to Snoul and Kratie or Sen Monorom
The motorcycle ride from Kampong Cham to Snoul is not with the best road equipped, but it's doable. Just before you reach Snoul there is a junction in the road with a police box on the right side. Follow the road to the left and you are on the highway to Kratie. You go through the town of Snoul just ahead where there is food and fuel.
Back at the junction by the police box just before you get to Snoul, following the curve to the right takes you to Mondulkiri. About 7 km past that curve you come to a four-way junction. Turn left there and you are on the dust highway (laterite surface) to Sen Monorom. Fuel and drinks are available at the four-way junction and 60km later, so you can bypass Snoul if you like. The road from Snoul to Sen Monorom is generally in good condition. It'sonly a dirt road but it's nice and level, because it was put in for the logging trucks. The road gets quite tricky during the rainy season, however, when the clay gets wet and it becomes similar to riding on ice. The scenery is beautiful and you're passing one of the remotest places in the country.