This Chinese museum proves that it's a watermelon world, we're all just living in it.

The history of radiation is on safe display at the foot of a radiation science laboratory.

A subterranean shelter remains intact under a busy Paris railway station.

High atop the Eiffel Tower is a small apartment built exclusively to entertain the science elite and make the rest of Paris jealous.

This iconic Parisian bookstore doubles as the "Tumbleweed Hotel" for traveling writers.

This 700-year-old street food market features baby octopus and soy donuts.

Tokyo’s only Vaudeville-cuckoo clock–steampunk-Victorian curio cabinet time piece.

A taste of the macabre Tokyo's ritzy shopping district.

South Korea's love of the silly photograph is on full display at this goofy collection of trompe l'oeil paintings.

Step into a cartoon at this Seoul café that aims to evoke a two-dimensional scene.

Visit the real-life site of the fictional pizzeria in Bong Joon-Ho's film Parasite.

Booksellers and public artworks fill this vibrant promenade along the disused railroad tracks.

Pulled from the rubble of one of the worst modern tragedies, a steel crossbeam became a symbol of hope for New Yorkers.

A one-ton statue of Steve Rogers beautifies the entry to a Brooklyn Bed, Bath & Beyond.

An exhibition space dedicated to American outsider art created between the 18th and 21st centuries.

This was one of the first (and last) university-built and operated nuclear reactors.

Every year model trains zip through a miniature New York City that's now 150 landmarks strong.

Here, exhibits come with a side of edible history.

This neighborhood grocery houses a treasure trove of Eastern European delights.

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

An annual extravaganza of Broadway theater memorabilia.

A hyper-luxurious, 12,000- square foot home might be buried beneath Queens, still waiting to protect you from nuclear missiles.

A WWI fighter plane and turn-of-the-century penny candy shop are among the unexpected features of this Financial District building.

A charming "tea atelier" hidden away in Greenpoint, Brooklyn.