In the past, Renaissance sex workers were encouraged to entice customers on this bridge.

According to tradition this is the oldest church in Venice, but its actual age is a mystery.

This palatial spiral staircase was so unusual the name "snail" was given to the noble family who built it.

The pile of books behind the dignified writer gave the statue a most undignified nickname.

This Roman statue is missing a limb from when the Venetians stole it from Constantinople during the Crusades.

Thousand-year-old Viking runes adorn an ancient Greek lion at the entrance to the Venetian Arsenal.

Skulls and skeletons are omnipresent in this church dedicated to souls trapped in purgatory.

This monumental fountain has moved around the city multiple times.

This medieval city gate is now a blend of the past and the modern world.

The Habsburgs' royal collections of art and wonders.

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

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

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

Op-art architecture designed for happiness.

The topiary maze at the Habsburg hunting lodge.

An early 20th-century bullring converted into a modern shopping center.

This home designed for chocolate magnate Antoni Amatller is an exquisite treasure-box of Catalan Modernism.

The iconic boulevard is the perfect place to catch sight of a bicycling skeleton, a levitating Satan, or a chef with his head stuck in a pizza.

A once-secret library of Freemason history in Catalonia.

A vista of the city and sea from atop the little-known viewing deck on an unassuming Columbus statue.

A cemetery in Barcelona's Poblenou district is home to this touching funerary statue, which depicts death in the form of a winged skeleton.

This former Baroque palace on the historic Calle Montcada is a rare architectural gem and was once the meeting place of an aristocratic scholarly society.

The 2,000-year-old Roman columns are hidden within Barcelona's Gothic Quarter.

Gaudí's famously flamboyant architectural style is on full display in this sprawling park and garden.