The feral felines of Roosevelt Island have a small army of allies and an abandoned hospital all to themselves.

A treasure trove of artifacts, books, and artwork from the "golden age" of exploration.

A crumbling hospital from the 1850s on Roosevelt Island.

La Monte Young and Marian Zazeela's "Dream House" will immerse you in an ever changing world of sound and light.

A nourishing complex of found object art, paintings, and sculptures that celebrate key figures in Black history.

Statue of Lenin, from Cold War era Czechoslovakia, now in a neighborhood of Seattle.

These strange large stones served as a campsite and lookout post for generations of Native Americans.

This Florida sinkhole hides a rainforest-like micro-environment in its depths.

A creative deviation in this post office's design was once a source of controversy.

From printing money to live music, this Beaux-Arts style building has had many identities over the last century.

This former factory has been transformed into a technicolor wonderland, where dozens of local artists have collaborated to create a real choose-your-own-adventure experience.

A luxuriant botanical garden below sea level.

This former prison is an Art Deco masterpiece with a past full of civil rights flashpoints.

The haunting remains of a failed housing development can still be found behind the big box stores that were to anchor them.

This state park was once an important Native American cermonial center.

One of only two pod-shaped homes designed by Frank Lloyd Wright.

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

A miniature rainforest is growing inside of a Midtown Manhattan office building.

A terrific purveyor of natural history objects and curios.

This rare basilica nestled right in downtown Asheville is an architectural marvel, inside and out.

This 1,500-acre development hopes to be the Central Park of the South.