Could maybe VRBO up by Harpers Ferry. Or go out to Shenadoah.

Go to the state park websites and do a search. There is one near-ish Aberdeen MD that was nice. Sometimes you have to book cabins pretty far in advance though.

Have friends coming from out of the country staying with relatives in central / southern NJ in early July. We'd like to get cabins or closeby VRBOs somewhere in the middle of the(ish)- a place where we can hike, grill out and do s'mores, maybe take the kids kayaking, horseback riding and other fun activities for a couple of days days. Ideally not too far from a cute town or restaurants. Would love some recommendations.