Architectureal fantasy quarter of Rome.

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

A towering monument in Spain has proven to be more labor-intensive than initially planned.

France's most famous cemetery, with some of its most curious tombs.

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.

A 19th-century politician who died after walking home in a blizzard is honored with this Manhattan statue.

One of only two commuter aerial tramways in the United States.

This monument to a veteran of the Mexican-American War is one of only two in Manhattan that serve as an actual mausoleum.

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.

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

A grand New York post office that is home to mailman Santas, scraps of postal history, and a pneumatic mail system.

A bit of retro transportation flair preserved in the world's largest department store.

Spinning silently in the lobby of an Art Deco masterwork is a massive vintage model of the Earth.

There are owls with glowing eyes in Herald Square.

Hidden in plain sight on a pair of Manhattan subway tunnels are a pair of public instruments that sing to each other.

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

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

Commemorating the spot where the famous scientist fed his pigeons.

The original toys that inspired the beloved children's stories are on display at the New York Public Library.

Tucked away amidst some of the most famous addresses in the world is New York's only fraction of a street.

This unmarked and unloved Manhattan subway grate created one of the most iconic images in American cinema.

A small peaceful park and waterfall tucked amid the urban grind of Midtown Manhattan.