42nd story Pyramid shaped penthouse tops Seattle's oldest skyscraper.

The cave where two British judges hid in exile after sentencing the king to death.

The old Niles Canyon Aqueduct in the San Francisco Bay Area is a bemusing and secret trail through nature for wayward travelers.

The only structure left with direct ties to the Salem witchcraft trials of 1692.

A 140-year-old castle with underground caves hidden in San Francisco.

Rippling sand dunes frozen in the Arizona rock.

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

A huge musical instrument played by the ocean.

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

A beautiful, dense forest in the shadow of Mount Fuji, with a tragic reputation.

The neon signs from Las Vegas' past find their final resting place at this unusual graveyard.

A crumbling hospital from the 1850s on Roosevelt Island.

Most-visited and most-photographed slot canyon in the American Southwest.

World's first "penitentiary," meant to be humane, drove men insane.

The rocks in this arid basin leave trails of movement behind them.

Dramatic river bend surrounds a natural red-rocked pedestal.

Dodge prohibitionists and slide through the telephone booth in Crif Dogs.

A collision of human error and natural geothermal pressure created this rainbow-colored geologic wonder.

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

An old vending machine serves up unpredictable beverages from its seemingly magical insides.

This abandoned subway station beneath the Waldorf-Astoria hotel is allegedly used to secretly transport presidents.

A roaring, awe-inspiring double cascade of icy water flows through woodland Oregon like something out of a Tolkien novel.