The first tunnel to be dug beneath a river, repurposed as an art and museum space.

Apartment complexes built into huge repurposed natural gas tanks.

An abandoned set from the 1980 film "Popeye," claimed and repurposed as a theme park by creative locals.

A 19th-century subterranean reservoir repurposed as a contemporary art cave.

Largest gathering of hobos in the country has been meeting annually since 1900.

This Parisian café sticks almost exclusively to an ethos of reuse.

The world's longest outdoor escalator takes visitors to the top of China's largest dam and is also shaped like a dragon.

Designed to serve primarily the Maharaja, this is an interesting variation on the traditional stepped well.

The largest puppetry museum in the United States houses the world's most complete collection of Jim Henson artifacts.

This narrow canyon has been carved by the river over thousands of years into spectacular and curious forms.

From Coke II to Google Glass, this exhibit features some of the most spectacular commercial flops.

Home to items never before seen by the public.

This beautiful Miami garden was designed as a laboratory for tropical plants.

Known as the "Hobbit Houses," these storybook homes look like they're straight out of the Shire.

London's creepiest cemetery was once the site of dueling magicians and mobs of stake-carrying vampire hunters.

Preserved Inca city and site of the last Inca stronghold against the Spanish conquistadors.

In Spain, the ruins of a Roman military camp sit along a flooded section of a river.

The longest living non-clonal organisms on Earth.

A natural dome made of volcanic glass in Inyo National Forest.

Living fossils in this remote Australian bay provide a glimpse of what Earth may have looked like 3.5 billion years ago.

An architect transformed this abandoned cement factory into his castle-like workshop.

Its front wall is striped with a menagerie of fantastic beasts and magnificent monsters.

The only diamond mine in the world where you can keep what you find.

On Japan's Tashirojima Island, cats are king.