Several islands outside of Boston, MassachusettsCamping offered:
$55.65-59.65/night (with ferry tickets)
On these ancient Civil War-era islands, you can tour abandoned historical buildings, wander through hiking trails, and then go kayaking or sailboating. The brave-hearted can stay in a tent without showers and electricity for a real camping experience. Alternatively, yurt rentals with electricity are available on Peddocks Island -- it’s just a 10-minute walk from fresh water and toilets.
Fun fact: Martin Scorsese shot scenes for Shutter Island here.