This small city where almost everyone lives in the same building can only be reached via North America's longest tunnel.

This ghostly Alaska village still clings to a steep cliffside despite having been abandoned for over 50 years.

This whimsical stacked cabin looks like something out of a children's book.

Mind-blowing carvings and fantasy ice scenes grace the largest year-round ice environment in the world.

Breathtakingly blue walls shimmer inside the "Glacier Behind the Town."

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

Crystal clear lake with a shoreline of travertine located in a Colorado canyon.

Wondrous sandstone hoodoos where Native Americans collected clay for pottery, 9,000 years ago.

An Escher-inspired library dedicated to the wonders of the human mind, yet closed to the public.

Yale University's home for rare works, including the mysterious Voynich Manuscript.

A religious-themed park filled with folk art to bring biblical stories to life that fell into disrepair and now being restored.

The king of U.S. high points towers over every other peak on the continent.

The highest point in Alabama was almost completely deforested, but is now home to protected towers and trees.

What began as an art installation is now the private drinkhaüs for a brewery's employees.

A once-thriving hotel in the Swiss Alps couldn't compete with climate change.

Traversing steep Alpine slopes, this engineering marvel is one of the longest and highest funiculars in the world.

This historic covered bridge contains a series of macabre paintings that communicate one thing: everyone dies.

A historic observatory precariously perched at the "Top of Europe."

The steepest classic funicular in the world glides along a dizzying incline.

This is not only one of the oldest collections in Europe, but also possibly the most beautiful.

This amazing pedestrian suspension bridge in the Swiss Alps would give Indiana Jones nightmares.

The tallest outdoor elevator in Europe rockets passengers on a dizzyingly precarious ride to the top of a mountain.

The bizarre visions of H.R. Giger, tucked away in a Swiss medieval city.

The original film set of Luke Skywalker's Tatooine home from the 'Star Wars' trilogy.