Just south of boston, theres an island called peddocks island. Its the best abandoned place ive ever seen. Theres a ferry that takes campers there during the summer, and is a short kayak from hull (they even rent kayaks). It was a military town in the 40's. Hospital, church, firestation, and woods with about two dozen houses and buildings. not really any artifacts left behind, and lots of poison ivy so be careful, but its a fun day if you pack some food and walk the old streets. I grew up in hull and can give details.