An opulent monument built for a duke who donated his entire fortune to the city of Geneva.

A nearly 500-year-old sculpture depicts a man eating a sack of babies, and no one is sure why.

A 1,215-foot tunnel transports pedestrians beneath the River Thames.

This wall on a street corner in Lower Manhattan has been a blank canvas for a rotation of renowned artists since the 1980s.

Whisper secrets in a busy station only to be heard on the other side of this acoustic arch.

A very classy 1920s-era bar right in Grand Central Station.

A dark patch of the ceiling at Grand Central Terminal which was not restored is still stained brown by tobacco.

This whimsical group of statues is a favorite of children who love to climb all over Lewis Carroll's beloved characters.

World Trade Center memorial likened to a woman's sexual organ.

This mosaic dedicated to John Lennon was tended for years by a Beatles super-fan.

Sniff the Titan Arum's rotting flesh.

Stunningly detailed mosaics in a New York subway station bring life to the Weimaraners of artist William Wegman's work—and to thousands of commutes.

An artist's cute bronze subway sculptures belie his violent artistic past.

Elevated freight railway turned wildly successful urban park.

The most confusing clock in New York.

The only subway station in the city that still makes use of gap fillers.

Skewer up Kangaroo.

A popular European tradition makes its way to the states on one of America's most famous bridges.

Wall Street has a new heroine, a bronze statue of a small but fierce girl.

The broken skateboards that became a poignant memorial to a murdered skater.

A contemporary art installation housed within a Gothic cathedral.

A cemetery for Slovenian notables also serves as a popular recreation space.

A whimsical bridge adorned with decorative dragons.

A trough of 700 strange bronze faces runs through a narrow alley in Ljubljana's old town.