I have made it from Mechanicsville to Sterling in 1 1/2hours. I have to plan it with the DC traffic and use my trusted backroads. But it can be done.
For "outsiders" you may be unaware of the Fall Line in Virginia. This is an upheaval area created by a meteor millions of years ago ~ and it left rows of concentric ridges all through the Mid-Atlantic. You get beyond the meteor upheaval areas it's pretty flat all the way to the Piedmont, so there are some segments of Virginia that have flat, straight roads just like the Midwest.
This area ain't one of them!