This giant boulder is sandwiched between apartment complexes in upper Manhattan.

This slender three-story building has also had several famous residents.

Imagine having a street run right through your home, or better yet, a historic bridge three stories high.

The artist and New York City icon lived, worked and died in this converted carriage house owned by another iconic artist, Andy Warhol.

A little lighthouse in New York City, surrounded by mysterious stories of insanity-driven construction.

There must be a pun in this haystack somewhere...

A whimsical, but often overlooked clock in Park Avenue.

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

Plot your trip through the city on the sidewalk.

One of the last few places in Manhattan that employed a pneumatic systemic keeps it on display.

A three-story copper skybridge connects two Manhattan buildings with Art Deco luxury.

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

A crumbling hospital from the 1850s on Roosevelt Island.

A beautiful and abandoned New York subway station from 1904, complete with chandelier.

Hundreds of glow-in-the-dark objects light up a museum in a historic zinc mine.

Climb this overlooked gem's spiral staircase and you'll be rewarded with spectacular views of Glasgow.

The Swiss artist's bulbous and overgrown shape-shifting sculpture controversially graces the center of Bern.

This enormous spiral sculpture looks strangely out of place on the edge of a housing development.

This high-design church is made up of two dizzying spirals meant to evoke the weaving together of marriage.

This dramatic landscape hidden on the Isle of Skye looks as though you've stepped into the magical realm.

Modern art meets modern convenience in possibly the world's most architecturally important public bathroom.

Norway has built what may be the world's most beautiful public toilet.

A clear example of the process of erosion in action.

Australia's largest medical museum featuring a 19th-century pharmacy.