7 one block west of the Mekong bridge roundabout. Departing at 8:00 and 14:00 with a 15 minute break. Also takes about 3 hours.
Most Minibuses and other non-Bus transports leave from or stop for a short time at the petrol station or just on the roadside of Highway 7 close to the Mekong bridge roundabout
Taxis are a less popular and more expensive method, costing about $10-$15 USD one way. These do, however, offer much more comfort and speed than a bus usually does, but make sure the vehicle's air conditioning is functional before getting in!
Trucks are also an option, but with much less comfort than buses or taxis, and are not advised.
Boat
Beware that boat services may have been discontinued completely.
As for all of Cambodia, there used to be also two types of boats in Kampong Cham: the slow boats and the fast boats. The slow boats are obviously slower than the other option, but are safer.
Slow boats don't have a pier, but simply land on the muddy river bank north of the bridge. Buy your tickets (for approximately 12,000 riel to eitherPhnom Penh or Kratie) underneath the huge cigarette advertisement. You can sit either on the roof or inside, and regardless of whichever you choose, you're in for a noisy, crowded ride. Get on the boat 1 hour prior to departure. To Phnom Penh the trip takes about 2-3 hours, to Kratie about 5-6 hours, with both boats departing throughout the day.
Fast boats are located on the riverside road, 20 minutes north from Route #7. These are more comfortable. As a result of the competition with road transport, however, there are no scheduled boats going to Kratie and Stung Treng anymore. Occasinally, there might be a fast boat doing the run. Kampong Cham to Phnom Penh costs 15,000 riel, and takes less than 2 hours, while to Kratie costs 20,000 riel and takes 3-4 hours
