There is always the C&D Canal Area for us Northerners.
Most areas are roped off, and you not allowed there, but there is one area on the South side of the Canal that appears to be some Sand Quarry or Fill dirt Area that I've been to many times. In fact, one time I drive right past a Park Ranger with my truck doused in mud and he just smiled and waved at me.

To get there, you go South on State Route 9 through Delaware City. Cross the C&D on the Route 9 Bridge. If you look forward and to your left, you should see it from the bridge. Once you cros the bridge, you make your first right-hand turn, and follow the road all the way back around to the Canal itself. At the T-Intersection on the dirt road, make a right, and you'll see a ramp leading to a dirt patch through the trees. Go in there and you'll see bulldozers and maybe a few trucks, and a very large dirt area. It's no Rubicon, but it's fun to splash the mud holes and climb the sand hills.

It's not a bad place to blow off steam, but don't start acting like a fool back there, or whoever owns it might choose to gate it off.
Use common sense and we can all enjoy it for quite awhile.
b