Several of these strange cone-shaped bunkers can still be seen around the former Nazi headquarters.

Now overgrown, these anti-tank barriers from World War II are sometimes called "dragon's teeth."

One of the only spherical 19th century gas containers left today.

This tri-part waterfall is a little bit of fairytale beauty in the heart of Luxembourg's Little Switzerland.

This medieval castle overlooking the Elzbach river looks just like it did hundreds of years ago.

This disused boat elevator was saved from the scrap heap so that visitors could tour its rusting skeleton.

The abandoned mine where American troops discovered a treasure trove of art and artifacts hidden by the Nazis.

A monument to the thousands of Canadian soldiers who died capturing the French ridge during World War I.

A top-secret bunker now turned museum, is an eerie look at what life would have looked like in the event of nuclear war.

A ruined castle stands atop a hill surrounded by dragon lore.

This temple to the sturm and drang of Richard Wagner contains a dragon's cave and reptile zoo full of living "dragons."

Preserving the research tools, unexpected inventions, and odd collections of generations of college professors.

These crumbling Nazi artillery bunkers are now fair game for massive graffiti projects.

This is what trains will look like after the zombie apocalypse.

Nestled in the woods lies this land art project: a hybrid between park, maze and natural monument.

The history of sea-faring refuse and disaster is on cramped display in this Netherlands folk museum.

The site where one of the most famous poems of World War I was composed is preserved to honor the legacy of the work.

This former Nazi castle was built as a school to train what would have been the future of the Third Reich.

The Bauhaus-style former industrial complex is considered the world's most beautiful coal mine.

This small town in the Netherlands has no roads but instead, miles of canals and over 100 bridges.

A fantastical bed and breakfast with magically unique rooms.

Museum in a swimming pool where the water still flows.

An industrial relic is now one of Europe's most staggering art spaces.

This former steel and coal plant is now a neon-lit industrial fantasia.