We rented one of these cottages a few springs ago and had a great time. It's very pretty, not that far from DC, the little town has a craft/art coop and a couple places to eat and feeding the goats and chickens on the property (plus, fresh eggs for breakfast) was fun. http://www.lostcitygoats.com/b-b.htm

We visited Berkeley Springs a few weeks back and it was great. There is a park there called Cacapon, where you can rent basic or modern cabins. An agency is available that rents out houses/cabins all around the area.

We've rented cabins in Berkeley Springs, WV and Lost River, WV via VRBO.com. Had a wonderful time - hiking, hanging out.

We love this place http://www.roseriverfarm.com/accommodations.html really great views, high end furnishings and less than 2 hours from DC. It is right near Old Rag Mountain, which is our favorite hike in Virginia.

I went here a few years back before kids were older and found it quite nice:

http://www.thewoods.com/index.html

May not be as rustic as you want though.

Shenandoah, near Luray. We've rented this one

http://www.mountain-lodging.com/starlit_view_log_cabin.htm
(it's in a clearing with 3 or 4 other cabins that are identical if you want separate cabins near each other). the road to get to this one is steep.

and this one
http://www.mountain-lodging.com/blue_ridge_getaway.htm
(which sleeps more. the Blue Ridge Getaway 2 is in the same clearing as well if families wanted to get separate cabins).

Check VRBO.com

Want to rent a cabin in the mountains with another couple, or two smaller cabins, within a couple of hours of DC. Virginia or PA would be our preference. Anyone have any good ideas?