indyfabz

One can never know. I have read some crazier ideas on BF.

Don't think you are going to find 50-70 miles of all off road in this part of the universe. Don't know where you are, but there is the Pine Creek Trail. You could start in Jersey Shore, PA (outisde of Williamsport, PA), ride to the north end through the Grand Canyon of PA, camp at one of the nearby state parks and then ride back to Jersey Shore the next day.

While not off road, the trip up the Delaware River is nice. Up the NJ side from wherever (L'Vlillle, Frechtown, Philipsburg) to Belvidere, cross into PA and continue north through Portland to Delaware Water Gap, PA. Cross back over to NJ using the pedestrian bridge along I-80 and take Old Mine Road for about 5 miles to the riverside campground in Worthington State Forest. Note that if you stay there and the bear boxes at the group camspites are being used, you will have to hang food. Did a day ride up that way in October and just missed seeing a bear near the campground.

There is the Columbia Trail, the north end of which is in Morris County near Mt. Olive. It then enters Hunterdon County, passes through Califon and terminates at High Bridge, which is very close to Spruce Run recreation area on Van Syckle's Rd., which has camping along the reservoir. If you need more miles you could stay in Van Syckles, make a left on NJ 173, take that into Clinton, pick up the Landown Trail, which connects to the Coopalong Trail, which takes you to Pittstown. From there, get on NJ 513 and take that all the way to Frenchtown. Cross into PA, go on down PA 32 for a few miles to Tinicum Park in Bucks County, where there is camping. Sadly, the camground at Bull's Island, about 10 miles south of Frenchtown, will not open this year. Part of it will remain closed forever. Part may re-open next year.

Lehigh Gorge State Park from Whitehaven, PA and then on road to Hickory Run State Park, which has camping. If you have Good Friday off, you could make it a 3-day and do a day MTB ride in the area.