Welcome to Aldie Park. There are 10 miles of trails here on 5.5 acres of nature preserve protected by Northern Virginia Conservation Trust. You're at the northern end of the Bull Run Mountain range. Just SE of the geocache is Aldie Mountian, which peeks at 700 feet.
You are looking for a medium lock-n-lock container decorated in camo duck tape. Inside are a log, pencil, and lots of buttons. Please feel free to take one, but a trade would be better.
Check the cache gallery for a photo hint and a fuzzy photo of the trail map.
No night caching.