Not necessarily legal, but no one has ever questioned me or any of my friends while up there. The land crosses the border from New Jersey into New York. The only times I have heard of anyone getting harassed by the law is when they have started a bonfire in the woods or excessively noisy vehicles that residence down the hill called and complained.
Go on YouTube and search Stag Hill Mahwah And you will find plenty of dash cam videos of trucks in there which will give you an idea of what you’re looking at
I’m really not sure. That whole area up there was once Indian land and some of it still is home to many descendants, but the houses are all much further down the hill.
The fact that it spans three towns and two states makes me think it’s unlikely it’s anyone’s private property. Watch some YouTube videos and do some research on the area And perhaps you can enlighten me.
If you look up Stagg Hill Road in Mahwah New Jersey on the Google maps, you can see where the road ends up in the hills, about a mile from the route 17 exit. From there it’s nothing but woods and rocky trails for miles .