An "inside out" building in the historical center of Paris, featuring Europe’s largest modern art museum.

This museum houses an imposing skeleton army comprised of creatures great and small.

This 1,300 year old monastery built atop a single rock was once only accessible depending on the whims of the tide.

The vast, legendary catacombs hold secrets much stranger than stacked bones.

A preserved college lock-up that recalls a clubhouse approach to discipline.

Sitting in the basement of a castle, the largest wine barrel in the world is bigger than most apartments.

Once the private home of China’s most legendary tycoon, getting inside this stunning mansion no longer requires an elite pedigree or acts of daring.

A nearly unconquerable island-fort in the Indian Ocean.

An ancient iron pillar in Delhi that seems to be rustproof.

An extraordinary "City of Caves" carved from solid stone.

This ancient Greek place of assembly and marketplace is being revealed layer by layer below the modern Athens cityscape.

A striking symbol of the Bulgarian capital.

This historic black and white monastery is one of Bulgaria's architectural jewels.

"Unity, Creativity, Beauty."

The picturesque birthplace of Icelandic democracy is drenched in the blood of its brutal past.

This stunning concert hall has become a symbol of Iceland's national recovery.

If a glacial river suddenly diving into a sheer chasm via a dramatic, multi-stage waterfall isn't peak Iceland, it's certainly close.

This eye-popping Icelandic crater lake is surrounded by red volcanic rock.

One of the tallest buildings in Iceland, and perhaps, the most visually impressive.

Medicinal spa created with the discharge from a geothermal energy plant.

Myanmar's Mount Olympus atop a 2,500-foot volcanic plug.

Over 2,000 ancient temples dot the Myanmar landscape at the site of this famed archaeological site.

This gem-encrusted temple is said to contain some of the Buddha's hair which can make the deaf hear and the blind see.

Teeming with illegal goods and services, this towering maze of vice is also a popular tourist accommodation.