Under the right circumstances, this waterfall in Yosemite briefly turns a luminescent fiery orange.

For two weeks every June, fireflies in the Smoky Mountains perform an astonishing light show.

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

This secluded aqua waterfall in the Grand Canyon is the perfect swimming hole, and the Havasupai tribe's fiercely protected natural wonder.

The abandoned zoo enclosures offer a perfect place to experience the other side of the bars.

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

Remants of foundations, streets, and streetcar tracks inhabit the cliffs where a landslide occurred in 1929.

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

An enormous, inside-out glass globe built in 1935.

An immersive environment that is part haunted house, part choose-your-own-adventure, and part jungle gym.

A snapshot of the city's fascinating voodoo culture.

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

A huge musical instrument played by the ocean.

Allowing humans and fish alike to migrate from freshwater to saltwater and back again.

Providing the soundtrack to the golden years of the Seattle grunge scene.

An enclosed rotunda at the Henry Art Gallery in which viewers can look up and see the uninterrupted sky.

Seattle's super-sized cowboy apparel once belonged to a themed gas station that wrangled in herds of tourists.

A nondescript Seattle restaurant inherited a piece of European history.

Residents of Fremont in Seattle have considered it the center of the universe since the 1970s.

From a neon Rapunzel to a bike traffic meter to a street fair color scheme, the most opened drawbridge in the US is a veritable art gallery.

The tech giant built three enormous glass orbs in Seattle so employees could work inside a rainforest greenhouse.

A (slightly) grownup take on the classic retro arcade.

This former coal gasification plant found a curious second life as a popular public park.

Doris Duke's lasting collection of Islamic Art, hidden in a Hawaiian paradise.