The only royal palace on U.S. soil has been a territorial capitol, a military headquarters, and a prison for a queen.

A Hawaiian stairway to heaven—that you can't climb.

During the solar phenomenon "Lahaina Noon" this bendy, curvy sculpture forms a perfectly circular shadow on the ground.

A cooled lava flow from the Haleakalā volcano formed these surreal-looking columnar basalt structures.

Get up close and personal with these majestic fish.

Climbing this abandoned railway leads to breathtaking vistas of O‘ahu.

This collection of grinning ephemera has grown from basement to Brooklyn.

The remnants of two World's Fairs are here, complete with a 12-story globe, a mini-Manhattan, and a UFO-shaped pavilion.

Sniff the Titan Arum's rotting flesh.

Mysterious 500-year-old tapestries depict a unicorn hunt.

The oldest surviving bridge in New York City, which reopened to pedestrians in 2015.

The one-stop shop for all of your superhero (or evil arch-nemesis) needs.

The oldest family-run luncheonette in New York, last renovated in 1948, still serves food and drinks the old-fashioned way.

Amid the bustle and noise of the Financial District hides a secluded garden oasis above the city streets.

This beautiful building in the heart of Manhattan's Financial District was empty for decades.

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

A tiny museum housed in a New York freight elevator specializes in the "overlooked, dismissed, or ignored."

A crumbling hospital from the 1850s on Roosevelt Island.

A beautiful and abandoned New York subway station from 1904, complete with chandelier.

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

More gold than anywhere else, ever.

Once the tallest building in the world and the site of "the highest dinner ever held in New York" this building now holds the most expensive penthouse in the city.

A masterpiece of LGBT art has been restored in what may now be the most valuable restroom in America.

This former crime corner has been turned into an eclectic community center.