Sals is a fantastic 10+ mile loop, with shorter inside loops of rocky, technical but well-flowing singletrack built by mountain bikers for mountain biking. A must do! See www.bikevmb.com and search under "trails" for complete info and trail map.
How to get there:
Rte I-78 exit to Rte US 22 exit to Rte 378. Take Rte 378 south to southside Bethlehem. Google Dodson St and take Dodson St uphill to the park. Start at the Park, its the most popular trailhead.