A submerged archeological park still holds the wonders of a Roman Sodom.

This Venice bookstore has resigned itself to constant flooding by keeping its books in bathtubs and boats.

A 16th-century horror show built in a lovely Italian garden.

An Italian crevasse filled with abandoned buildings gives visitors a look at the world without humans.

The crypts of Capuchin friars decorated with the bones of over 4,000 friars, including an entire "crypt of pelvises."

Two nations form a rare four-sided border at the peak of a mountain, philosophical questions result.

Austria's very first and only nuclear power station was completed but never used.

This spire on an Austrian mountain is wrapped around a long spiral slide and has the world's tallest wooden observation deck.

A breathtaking viewing platform over the Alps.

Fantastic stories on a miniature railroad.

A unique opportunity to stay the night in retrofitted sections of sewer pipe.

This 19th century cyclorama acts like an analogue time machine to a different era.

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

"World machine" built by an untrained Austrian farmer.

The world's oldest known salt mine.

Resting in the middle of an Austrian river, this sci-fi "island" lets people cross in neon style.

American soldiers discovered Europe's best one-liner at the end of World War II.

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

The beautiful baroque library of the Hapsburg empire.

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.

Ride a dragon train into a world of dwarves.

Inside the corridors of this flea market, visitors are sure to find some obscure and odd treasures.

A neo-Gothic mansion now houses a wunderkammer of analog tech that hits on all the senses.