4. Fort Tilden

An abandoned military base by the ocean sounds like an urban explorer’s dream or a poetic device, but it really exists at Fort Tilden, the ex-Army base that is now being reclaimed by nature. The fort was constructed way back in 1917, and it served as a fort in both World Wars as well as the Cold War. During World War I, it housed ammunition hoists, electric lights, and telephones. During World War II, over ninety new buildings were added to the fort, and it later became a centerpiece of American defense.

The area is full of the hulls of silos, and visitors can see the huge concrete batteries built into bluffs, each of which housed a 70-foot-long cannon way back when. It’s now a natural area of beach and maritime forest; a labyrinth of abandoned rooms and amphitheaters also hosts the odd art installation or performance.