This 170-year-old Swiss guesthouse built into the side of a mountain is best accessed by a cable car.

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

This noble mash-up in eastern Luxembourg is part Medieval, part Renaissance, all castle.

This Luxembourg cave is covered in cryptic looking marks left by mining activity.

Two standing giants remain as a tribute to Luxembourg's metallurgical past.

In the heart of Luxembourg's "little Switzerland" weaves a breathtaking natural sandstone canyon with a mythological past.

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

An expansive complex of subterranean tunnels is all that remains of one of Europe's most formidable medieval fortresses.

Once the local rulers had gone these enchanting ruins housed common folk in an almost real life fairy tale.

Once the home of a hermetic monk, this cave now houses a small church.

This Hungarian castle was built out of cardboard and wood until it proved so popular that it got upgraded to stone.

Built in 1870 at the bridge that connected Buda and Pest, this spectacular incline railway was almost lost forever during World War II.

A trail of iron footwear stands as a monument to the thousands executed along this riverbank during WWII.

A 19th-century artistocrat's mansion, turned into a library, hidden in a modern library.

A series of caves under Castle Hill that once held the prisoner Vlad Tepes, better known as Count Dracula.

This Budapest bar allows drinkers to leave their mark on the walls, floor, and even ceiling.

A tropical paradise just a short trip from the opera house is filled with beautiful winged creatures.

A small museum filled with over 1,000 clocks, and one particular clock calibrated to run until the year 9999.

Built to give thanks for the passing of a plague epidemic, this cathedral is a one-of-a-kind architectural hybrid.

Macabre museum devoted to historical Viennese murders.

The final resting place for the remains of 143 Habsburg royalty.

The crypt of the imposing Stephensdom holds royal intestines and thousands of skeletons.

The beautiful baroque library of the Hapsburg empire.

Walk through Czech history in Prague's largest graveyard.