No need to strap in for a "ride" on this walkable roller coaster.

This steel frame is a skeletal mirage of a lost 16th-century stone building.

Live out your childhood construction fantasies in this one-of-a-kind gyrating hotel.

The 20-mile causeway that separates the Netherlands from the sea.

Rich with fauna and flora, nature-lovers can walk across the sea at this UNESCO World Heritage spot.

Found art has transformed this Pittsburgh neighborhood into a psychedelic dream.

A pixel art killer whale is frozen mid-leap in this Vancouver square.

Travelers exchange letters with woodland creatures at this mini post office.

One man's prolific, decade-long quest to turn trash into artistic treasure.

A pier that used to act as a busy ferry dock is now a decaying favorite of local fisherman and urban artists.

A playground built by the kids that is a child's wonderland, and a helicopter parent's nightmare.

After serving in World War II and picking up Apollo astronauts, this aircraft carrier has been turned into a museum overlooking the San Francisco Bay.

A unique piece of graffiti offers a little slice of local history and mystery.

A "gravitational anomaly" located in the redwood forests just outside of Santa Cruz, California.

This Big Sur waterfall drops 80 feet directly into the Pacific Ocean, and inspired the hillside house up top.

This stretch of beach along California's central coast is a busy highway for the largest seal in the northern hemisphere.

A massive volcanic plug is now a protected area that hosts a number of bird species.

Legendary frontman of the Doors looms in this giant mural by famed Venice muralist, Rip Cronk.

An historic and oft-filmed spot for musclebound iron pumpers on the Pacific coast.

A sign at the end of the Santa Monica Pier marks the traditional end of the legendary American highway.

A sculpture of the famous photograph stands on San Diego's "Greatest Generation Walk."

Medicinal spa created with the discharge from a geothermal energy plant.

This tiny museum's sizable collection is jammed into a former underground public toilet.

An encyclopedic collection of mammal penises.