In the middle of a Vienna square, Roman ruins dating back some 2,000 years are on display.

The first modernist church in Europe.

The solemn exterior conceals an opulent interior of this 17th century church.

Vienna's diversity-themed traffic lights were inspired by the Eurovision Song Contest.

An exquisite Baroque church in Vienna's old town.

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

Legends surround an ancient tree trunk riddled with nails for good luck.

A silly medieval mural preserved on the side of a Viennese house.

Baroque celebration of the end of the Great Plague of Vienna.

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

These are probably the most beautifully-crafted toilets you've ever seen.

This strange statue features a bust of the famous composer plopped atop a woman's body.

The beautiful, ornate weather station is the most popular geocache in Salzburg.

This skeleton-filled altar piece served as a backdrop to one of the most iconic scenes in "The Sound of Music."

Amidst medieval and baroque buildings, five human-sized gherkins stand tall.

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

Ugly 18th-century dwarf statues living in a perfectly landscaped Austrian garden.

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

Memorials at a Florence railway station remember the citizens who were deported from Italy and sent to extermination camps.

A 16th-century fountain marks the site of a lost medieval cemetery once filled with mass graves.

The water-powered carriages are long gone, but for over a century this funicular railway has been the fastest route to the highest point in Paris.

The site where two doves fell in love.

One of Jeff Koons’s largest sculptures and his first commemorative work.

If you look closely at the oldest bridge in Paris, you might notice hundreds of ugly faces leering from its sides.