Travel through the hidden underbelly of the city in colorful tunnels filled with art and history exhibits.

An immersive art experience built by local arts collaborative, Factory Obscura, in the building formerly known as The Womb, a psychedelic arts center founded by the frontman of the Flaming Lips.

A grove of "candelabra redwoods" deep in California's Lost Coast.

Resting place of Hollywood's immortals is also site of summer film screenings.

Giant busts of 42 U.S. presidents are sitting in a field in Virginia.

The land is full of geologic eye candy, such as otherworldly spires, mushroom-shaped hoodoos, and prehistoric fossils.

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

The only swimming pool listed on the National Register of Historic Places is emptied and refilled each day with naturally filtered water.

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

These remote Florida islands have a history of sea turtles and sunken treasures, and one of the world's largest coastal brick fortresses.

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

Dramatic river bend surrounds a natural red-rocked pedestal.

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

This jaw-dropping 19th-century bridge uses its reflection to form what appears to be a perfect circle.

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

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

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

Hike amid the palm trees that thrive among Southern California's Indio Hills.

Thousands of pieces of art have been carved into the rock at the site of an ancient volcanic eruption.

Caves famous for the dragon-slaying saint who lived there.

The vast, legendary catacombs hold secrets much stranger than stacked bones.

For over 300 years this little carving has been the city’s good luck charm.

A hands-off space for graffiti artists to hone and display their skills.

The fierce beast perches atop a pedestal marking where the historic City of London gates once stood.