This narrow coastline trail through the dense Kauai wilderness is among the most beautiful and dangerous in the world.

Submerged lava formations create incredible waterworks.

Climbing this abandoned railway leads to breathtaking vistas of O‘ahu.

A series of waterfalls and pools that flow through the 'Ohe'o Gulch and into the ocean.

This industrial area was the dumping ground for massive amounts of trash, some of which washes up as tiny bits of sea glass.

A beach made of semi-precious green sand on the Big Island of Hawai'i.

These picturesque Hawaiian falls are home to a rare species of fish that uses a special sucker to climb up cliffs.

Earth's tallest volcano is sacred to Native Hawaiians, and home to a dozen world-class observatories.

This black shoreline is made up of exploded lava particles.

Mariners once used this prehistoric landfill as a navigational landmark.

A monument celebrating the idea of reaching inaccessible places.

Island ghost town detailing Flagler's folly in building the Overseas Railroad.

A hidden beach at the end of a tunnel of mangrove trees.

When ecosystems collide in the arid Southwest.

The superstar of Cold War nuclear bunkers has been featured in countless films but is now barely operational.

This naturally-sourced hot spring is now home to a clothing-optional resort.

At this Denver landmark, the meals are compulsory, the sopapillas are complimentary, and the insanity is everywhere.

Art in the form of a winding, man made crack in stone.

This concrete tangle of square pipes has stood as a proud thorn in the city's side since the '70s.

The seawater playground of gilded-era San Francisco burned to the ground in 1966.

Get lost in this haunting fairytale art walk through a man-made eucalyptus grove.

An artsy hidden staircase leads to breathtaking views of San Francisco.

An iconic location along the Los Angeles River where countless movie scenes are filmed.

This brightly made over hotel hides decades of suicide, serial killers, and mysterious deaths.