Rainbow-hued local gem in Venice.

Home to items never before seen by the public.

A tiny piece of the Moon is embedded in this stained glass masterpiece.

The first and only carousel with a lineup entirely of insects.

The loneliest island in New York.

The end of the 4 Line is also the end of the line for 300,000 souls in one of NYC's most illustrious cemeteries.

This free, take-a-book shop seems like a trick but isn't.

Walk through the history of American pop culture.

Stained glass windows bathe this botanical garden in cosmic light.

The winter home of millions of migrating monarch butterflies.

A jaw-dropping "megalibrary" that turns book-browsing into a geometric adventure.

Underwater art project will double as a massive artificial coral reef to help regenerate the damaged ecosystem.

An organ located deep within a cave, whose "pipes" are the geological features of the cave itself.

A pedestrian island in the middle of world-famous Times Square emits a strange (and purposeful) humming noise.

The intricate stonework of Machu Picchu serves as a testament to Incan engineers.

This Elizabethan hedge maze is one of only six in North America.

Equal parts record-breaking temple to consumerism and bizarre fun park, it's more than you think it is...

The last moments of the ill-fated Pompeiians, frozen forever in plaster.

Breathtaking and huge 430 year old maps of Italy.

Go inside to really appreciate this 500-year-old technological masterpiece.

Abandoned medieval hill town.

Winding paths and ramshackle mausoleums in the oldest "park cemetery" in London.

Ruins of a 10th century church tucked away deep in a botanical garden.

The second-largest cave chamber in the world was discovered in 1898 by a 16-year-old and a friend known as "Pothead."