There currently about 30 climbing locations listed.
With the exception of some boldering in the Sourland Mountains and near Princeton and a couple of places on the first range of the watchung mountains that are closed or difficult to reach all are north of I-78.

Rock Climbing Routes in New Jersey|
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Delaware Water Gap NRA, (Mt.Tammany), Most 2 pitches, 1 3 pitch (Black Wall - 120 feet)
Allamuchy State Park - 60' 5.5-5.11b
Sourland Mountain Preserve (Somerset Co. Park) V0 - V8 bouldering - Currently Closed
Witherspoon Woods Boulders V0-V6 - Near Princeton

Smaller areas in Central NJ:
South Mountain Reservatin (Esssex Co. Park) - Turtle Back Rock 5.3-5.8 - Hemlock Falls 10-15' 5.7-5.9d
Mills Reservation County Park (Exxex Co. Park) - 45' 5.5-5.9
Watchung Reservation - Seeley's Rock | - 20-30 feet - 5.7 - 5.11a - Prohibited Now
Middlebrook Heights - Washington Valley Park (Somerset Co) - First range of the Watchung Mountains, Martinsville - McBride's Rock - 12-19 feet 5.5-5.8 - Not specifically approved

last updated 10 Sep 2018