The fountain marks the area where hundreds of accused witches were burned at the stake.

The history of occult science is turned into a creepshow at this lurid Prague tourist attraction.

The site of Austria's biggest concentration camp now honors its victims.

This "mathematical tower" was an observatory, early skyscraper, and place to reflect on all of nature and the cosmos.

A history of heat is on display at this unique Austrian museum.

Vienna's underworld of tunnels and subterranean rivers made an iconic appearance in a 1949 Orson Welles film.

A neo-Gothic church built to thank God for saving the Emperor of Austria from an assassination.

The medieval network of canals hidden underneath the city is opened to explorers each year.

The world's oldest known salt mine.

The townhouse where the "Blood Countess" Elizabeth Báthory started her murderous career.

Giant WWII fortresses that fired 8,000 rounds a minute, now home to thousands of pigeons.

Double spiral staircases are not unheard of, but they are very rare.

This series of underground chambers contains Europe's largest subterranean lake that is slowly drained each day.

The world's largest collection of intentionally useless inventions.

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

Op-art architecture designed for happiness.

A spherical "micro-nation" in the heart of Vienna.

Located right outside of Vienna, visitors can take in expansive views of an ethereal forest.

This Austrian museum celebrates the work of famous forgers and their inimitable imitations.

The largest ice cave in the world is thought to be the entrance to hell according to Austrian legend.

The former private quarters and office of Dr. Sigmund Freud now hosts a museum housing the works of the founding father of psychoanalysis.

The topiary maze at the Habsburg hunting lodge.

A centuries old castle atop a dormant volcano houses museums devoted to both women and witches.

An Austrian house of bones filled with hundreds of intricately painted skulls.