When ecosystems collide in the arid Southwest.

Hidden beneath a bridge, this waterfall is known for the large amounts of graffiti painted on its base.

The largest self-built castle in the U.S., six decades in the making.

A breathtaking array of ancient Pueblo structures and artifacts counterintuitively preserved by neglect.

Crystal clear lake with a shoreline of travertine located in a Colorado canyon.

Wondrous sandstone hoodoos where Native Americans collected clay for pottery, 9,000 years ago.

This eclectic collection documents the wild legacies of "America's Wickedest Street."

Where scientists keep miles of very valuable ice from Antarctica and Greenland from melting.

An abandoned subway tunnel that could have reinvigorated Staten Island still lies somewhere beneath this Brooklyn park.

I fought the law and the precinct caved in.

Underground vaults of a former brewery beneath Brooklyn's Crown Heights are now used to ripen cheese.

This interactive gallery makes you feel like you've stepped into a fantasy world filled with whimsical monsters.

A no-frills cinephile haven known for showing offbeat, underseen films.

An arcade packed with a rotating collection of unique independent video games.

Check out the underground party scene at the "Burning Man of Brooklyn."

In the middle of downtown Brooklyn lies a 165 year old secret hidden right below the surface (closed to the public indefinitely).

A charming "tea atelier" hidden away in Greenpoint, Brooklyn.

This innocent-looking townhome is actually a subway exit.

Just your average Marie Antoinette–themed speakeasy in an abandoned 19th-century subway tunnel.

Detailed facade of a brownstone in Boerum Hill.

Abandoned power station once home to a squatter community, now being developed into an arts center.

First a horse rendering plant, then a 19th century landfill, this beach is full of glass from thousands upon thousands of broken bottles.

Leaf through over 30,000 artists' sketchbooks in what may be the world's largest collection of doodles

Behind a bodega is a small museum of relics and ephemera showcasing the history of New York.