A tree planted by Marie Curie is treasured by the Radium institute that she set up.

The final resting place of the last "gypsy king" of Poland.

This biographical museum honors the groundbreaking scientist at her birthplace in Warsaw.

Guests become prisoners on a visit to Latvian prison.

The two abandoned overpasses are among the largest bridges in Poland.

A whimsical sculpture garden right out of a children's storybook.

A naturally beautiful, seemingly bottomless deep blue spring.

One of the largest single-span stone-arch bridges in the Balkans looks like something straight out of a fairytale.

A medieval bridge stretches over a sulfur-rich river that leads to year-round natural hot springs.

This wrecked ghost ship has been rusting on a Greek beach since the 1980s.

Perched on a spindly rock spire in a Greek archipelago, this lighthouse would make a perfect wizard's tower.

Replicas of Apollo's leonine stone guard cats still line a sacred row in Greece.

This abandoned Greek island was the last active leper colony in Europe.

This little Greek plateau is home to thousands of rustic, white-sailed windmills.

Hungarian mummies in beautiful painted coffins.

The abandoned "Red Star Train Graveyard" is the final rusting place for precious artifacts of train history.

Despite being pillaged and destroyed a number over times down the centuries, this historic church still sort of stands.

Climbing to the top of the cathedral's bell tower offers sweeping views of these medieval ruins.

Romania's "Red Ravine" is a little-known natural wonder that bears a resemblance to the Grand Canyon.

This Romanian village may have been drowned, but it is long from forgotten.

The Natural History Museum that time forgot.

Some call this eerie forest of crooked trees the "Bermuda Triangle of Romania."

Inside the Šomoška National Nature Reserve exists a unique rock formation rarely seen in the world.

Gliwice Radio Tower, likely the tallest wooden structure in the world.