Every Christmas, one Arizona city makes the most of its dry climate by creating an arid desert tannenbaum.

A self-built castle made by a mysterious man.

A mysterious "wedding cake" castle in the middle of the urban desert.

The first permanent memorial to a unique secret weapon of World War II.

Open since 1938, this diner has kept its fountain, malt machine, and all the gum that greasers left beneath its counter.

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

A former department store turned into a quirky restaurant.

This striking public art installation is suspended above a public park, designed to gently move in the breeze.

The most powerful waterfall in all of Europe.

One man's ambition created this psychedelic log home.

The highest point in Montana is as rugged and singular as the state itself.

A 1940s nuclear reactor built to produce plutonium for the Manhattan Project.

A fine, large-aperture telescope available for public use.

A tourist attraction founded around a slumping cabin.

A public fountain that spouts "health water" from a nearby spring.

Formerly secret, precariously perched boulders.

This extravagant Art Nouveau rest stop features a million-dollar view of the Columbia River.

The longest continuous lava tube in Oregon.

Bridges, terraces, and replicas of historic structures all built of rock and petrified wood by one man.

The longest continuous lava tube in the continental U.S. offers 2.5 miles of dark explorations for the adventurous.

Featuring a casually threatening atmosphere along with dessert and coffee to die for.

Private collection of art inspired by cabinets of curiosity.

Is this the most Portland place ever?

A heavenly experience, right here on Terra Firma.