A few miles south of the Big Bend campground, Jess Judy is a primitive national forest campground offering 3 group sites. Although Big Bend offers more amenities, with flush toilets and showers, Jess Judy is a more economical option for a group. You'll need to check in at Big Bend.

The sites are grassy, with areas mowed into the larger field, with hills rising above the campground. Vault toilets are located nearby. Picnic tables, fire pits, and grills are provided. Drinking water is not available, so bring your own. 

The Potomac runs through the canyon and provides fishing opportunities. there are also hiking trails. Smoke Hole Caverns (40 minutes away) offers more touristy attractions such as mini gold and a cavern tour (ok, not spectacular). The Seneca Rocks area is more than an hour away. Shreve's country store (<3 miles) may have some items if you've forgotten something, but not major shopping. 

I didn't explore it, but the North Fork Mountain Trail receives rave reviews for spectacular views and if you can run shuttles, you could hike portions of this.