The trail surface is dirt not rocks, making for a flowing, IMBA-type singletrack through jungle-like forest in the middle of Pennsylvania's capital city. There are taverns at the start and middle of the trail. Overall, a very unique and unusual ride.
Family Friendly: No long climbs and a level paved bike trail always close by.
There is a crossing on a concrete "ford" that is very shallow (when I rode it), but slippery. It can be bypassed on the greenway bike path.
The packed dirt trail bed is smooth and flowing with many tight berms and some off-camber corners. Expect short steep climbs and descents, log piles, and other interesting features including a paved ford.
Occasionally, it is necessary to pop out of the wooded ravine into the city to cross a major street. Other places you're 100 feet up, clinging to the 12 inch tread at the top of the ravine wall. The paved Greenbelt bike trail runs through the system like a spine and provides an easy bailout everywhere.
Maps of the entire paved trail which loops all the way around the city are downloadable at CSGA.org, but they do not show the singletrack. They do show available parking. There are additional segments of singletrack not shown on the MTB map and more trail under construction.