After arriving in Phnom Pehn we thought we would fly but then the ticket price for the flight we wanted went way up. The hotel arranged for a taxi to take us to Siem Reap for $75. We had a good driver and I am not sure how he could have made it any faster. It took us 6 hours with a small stop in between. There were maybe 2 cars that passed us the whole time.

For those who might read this thread in the future. Part of the road is paved and part of it is dirt. It looks like this road will be under construction for a very long time. There were parts of the road that they were working on but it did not look like they were in a hurry to finish any of it. You do drive by a lot of farms, fields, and small towns. You see a different way of life. There were a lot of cattle (sometimes in the middle of the road), buffalo, hogs, chickens and other farm animals.
I would not want to be on this road at night. Trucks, cars, busses, motor cycles, bikes, pedestrians, hand carts, and sometimes animals all share the road.