At any rate, we are booked at pohick bay. From what I have found, we can drive to mt. vernon when we want to do that, or to the metro station to go into DC. I also saw somewhere a suggestion to take the VRE into DC as well, which may be easier. Worst case I guess we drive in.
I understand about the weather. I fully expect it to be hot, and I know we will have to deal with hydration and trying to keep cool. In the few years we have been camping, I've learned not to worry too much about the weather. If I did that, we wouldn't go anywhere. Everytime I've "worried" its turned out to be better than I thought. Everytime I haven't we have figured out how to make the most of it. The bigger challenge is getting the rest of the family on board with this thinking.
I'm still trying to figure out the best way to get there. Since it is a long drive, we will likely leave the night before but late, to utilize the coolness of the night and the fact it will be friday before a major holiday. This may put us at our destination before "check-in" time, but I'm sure we can figure something out, even if its paying for a different site to sit on for a few hours...wouldn't be the first time.
My overall goal is to stay away from 2 lane roads and construction. Or those combined lol. Not always the easiest thing. I actually don't mind lesser traveled 2 lane highways even if they are slower...we often use them in our travels around ohio. But I also don't want to add lots of "hours" to what is already going to be at the very least 9-10 hours of driving, plus some rest time in the middle.