Collapsing castle on the Hudson river was once the storage site of military surplus business.

A stunning, two-tiered waterfall made famous by poets, artists and the legend of a ghost dog.

Hidden in Central Park's Ramble is a troublesome cave buried just beneath the surface.

A Pythagorean funhouse that tries, successfully, to prove that math is the coolest thing ever.

A decaying garage hidden amid the dense forest is all that remains of a once-prosperous dairy farm.

The only place for a truly presidential dram.

An innovative attempt to break a siege in the American Civil War still scars the earth today.

Hop on the train and tour an elaborate miniature town made completely of junk (including the train).

The Virginia home of one of the signers of the Declaration of Independence is being preserved with a unique glass facade.

The oddly shaped, steam-spewing building is now an art studio and gallery.

Lines from a walking song are etched into a rock in Natural Bridge State Park.

The skeletal white beams stand as a monument to religious dissent.

Heron, whitewater rapids, and urban industrialism all add to the beauty of this concrete nature walk.

This once-palatial plantation may have been the site where a draft of the Declaration of Independence was written.

Exact replica of the ancient monument, but much, much lighter.

The flower-shaped temple in Virginia aims to transcend the boundaries of the world’s religions.

Outsider art meets paleontology at this roadside reptile repository.

A sacred site for Native Americans surveyed by George Washington and owned by both King George III and Thomas Jefferson.

The remains of a failed attempt at medieval nerdery are hidden deep in the woods of Virginia.

Giant busts of 42 U.S. presidents are sitting in a field in Virginia.