A walk through the historic city center, under the streets of Seattle.

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

A bizarre house filled with an astounding array of collections.

Dramatic river bend surrounds a natural red-rocked pedestal.

The macabre collection of Jacques Sirgent, an expert scholar on the undead and all of their trappings.

The installation’s official name, “You Who Are Getting Obliterated in the Dancing Swarm of Fireflies,” says it all.

A theme park that suffered massive flooding during Katrina was abandoned, and now proves irresistible to trespassing explorers.

These old stone ruins in the Oregon wilderness were once bathrooms and are steeped in legends of murder.

On the Oregon coast there is a natural hole that seems to be draining the sea.

Bring your own cardboard to the slippery slopes of concrete hidden in a neighborhood park.

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

Rippling sand dunes frozen in the Arizona rock.

This astonishingly geometric cave has inspired everyone from Jules Verne to Pink Floyd.

A kaleidoscopic warehouse-maze of handmade neon signs.

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

These pretty kitties killed and ate as many as 135 railway workers.

This shop for all your super spy needs hides an educational secret.

A speakeasy takes on Chicago's drinking culture.

A lush green oasis in the middle of Chicago.

This massive stained-glass masterpiece is thought to be the largest Tiffany dome in existence.

Sloth rehabilitation center in the jungle of Costa Rica.

This Costa Rican topiary park is a surreal garden of unearthly delights.

A stunning, abandoned limestone quarry in southern Indiana provided the stone to erect the Empire State Building.

The Fun Farm weaves fairy tales, myths, and magic into a magnificent collection for visitors to explore.