If you have ANY extra time we highly recommend visiting this national park. In late October, foliage will be near-peak with breathtaking reds, oranges, and yellows. The closest entrance is Thorton Gap, just 15 minutes from Luray. A pass into the park is $30 per vehicle (good for seven days). It is well worth it!
If you're looking for something more lowkey than SNP, check out the nearby state park. It features some beautiful views and easy hikes that would be good for kids and families. The park is a quick 20 minute drive from Luray. Entrance fee is $10 per car.