First stop, check out the Northeast section of the forum:
North East Region - Toyota FJ Cruiser Forum
There are get-togethers and trail runs listed throughout the year in this section.
Rouch Creek Off-Road Park near Tremont is a great choice for a stock FJ. It's about 2 hours northwest of Philly.
George Washington National Forest is 5 hours south on Interstat 81. Very pretty and many clubs on here stage runs/campouts there.
Look up Baltimore 4 Wheelers. They are a very active club and well-organized.
Have fun!!
M
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"That seems to be when you're in your element and at your happiest. ...just an observation, but put a winch line in your hand in a boreal forest, a muddy woodland, or an arid desert and the word harmony suddenly makes sense

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Dragon
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2007 FJ Cruiser
1989 4Runner (under renovation)