This trail is very challenging. It is more of a hiking trail to the top of a mountain. There are a variety of less difficult trails {Central, Laurel, Cabin, etc.} at the bottom of the mountain. However, if you hike and hike your bike 2-3 miles to the top on Ziler Loop you will be either rewarded or tortured with very difficult downhill singletrack. The downhill is extremely rocky, intricate, and steep. If you are willing to walk up to challenge yourself and your bike, you will be able experience complicated shale covered descents littered with switchbacks and thorny rock sections. It was worth doing it once this season and maybe once each season, but the climb to the top almost makes it not worth the descent. {I am referring to ziler loop up and then the zig zag ziler trail on the map down} There are other trails that I did not get to explore, which seem less challenging but still very rocky and beautiful.
From Washington DC take the Beltway to I- 270 North, Merge onto I-70 West toward Hagerstown, Merge onto US - 522 South to Cacapon Resort State Park.
http://www.singletracks.com/item.php?c=1&i=2299