Power lines are private property, without permission you 'could' get in trouble driving on them. NEA clubs really don't like to see the damage done by renegades that go 'muddin' in power line access roads. Any (and all) Class VI (six) roads in NH are by law, open to anyone most of the year. Cannot legally be blocked...there are a lot of offroad clubs (jeep & other vehicles) in the state-you just have to find them-and see what's up for offroading. Jefferson is sitting in the White Mountains-most of that is federal park land-so NO offroading, period. The big state 'offroad park' up in Berlin isn't for jeeps and 'road type' vehicles-lot's of complaints made to the state about discrimination against us 'jeepers' and such but the state won't give in...even though WE pay state taxes and fees with our registrations...snowmobiles and ATV clubs get what they want.
Plenty of offroading over here in Sullivan County and other 'western NH areas, NEA4WD has private properties all over with good trails...Fall Crawl is in a couple weeks down in Hancock/Dublin area, might be some tickets still available for some of the runs.
Mass. clubs come up in gangs to join in...
Northeast Association of 4WD Clubs