If you drive route 287 in Northern New Jersey, you probably see a bridge over the highway that says "Cannonball Trail".   This is it. You can get on it from the Ramapo Mountain State Forest, or from a parking area in Oakland

The only problem with this trail is that it is connected to the road system in the forest, where the Mountain Bikers can get easy access to the trail.   It really  doesn't make for a good experience, unless of course you like hiking in traffic.  The bikes really tear up the trail and the environment, making the trail look more like a road.